Not capturing...

[Rainier]

Hi, we're trying Fiddler everywhere on OSX Mojave, as a replacement to Charles, and it seemed to work when first installed as I got the password prompt, but upon relaunch it now no longer prompts for a password. Clicking the 'Capture button also does nothing.

Any ideas?

Thanks

[Rainier]

I should have mentioned I've also tried to launch fiddler with:

sudo /Applications/Progress\ Telerik\ Fiddler.app/Contents/MacOS/Progress\ Telerik\ Fiddler

[Dimitar]

Hi Rainier,

I have a couple of questions I need to ask you in order to have clearer understanding of what the described scenario is.

1. Fiddler starts without prompting you for a password. Do you eventually get the password prompt after clicking the capture button?
2. Does the issue persist when opening Fiddler at a later time? ( either from terminal or by clicking the Fiddler icon )

If this issue persists, it will be very helpful if you send us Fiddler's logs folder ( located in %temp%/Progress Telerik Fiddler/Logs ) to help us narrow down what the problem is caused by.

Regards,
Dimitar
Progress Telerik

[Rainier]

Hey!

1. I only ever saw the password prompt once, upon first launch and enabling of capture. It's never prompted me again, despite having launched Fiddler countless times and also clicking the 'Capture button as many times too. Note that clicking the 'Capture button does trigger an action, as it turns blue as the mouse button is pressed, but returns to standard UI colour when I release mouse button and capturing is not enabled. 

2. The issue persist no matter method of launch or how often I launch Fiddler.

One other observation - If I hit the capture button, and then shutdown Fiddler completely, it generates an unhandled js exception. If I simply launch and then shutdown Fiddler without clicking the 'Capture button, no exception. This is consistently reproducible. See attached screenshot.

Attached logs(open $TMPDIR) show a socket exception and internal 500. Please rename from .png to .zip.

Thanks

 

 

[Rainier]

Hey,

1. I was only ever prompted for password the once, upon clicking 'Capture the very first time I enabled it after install. Never seen a password prompt again however.

2. Issue persist regardless of how many times I launch Fiddler since having installed it a week ago.

Note - The 'Capture button does appear to trigger when I click it, as it turns blue. But as soon as I let go of the mouse button it turns back to default UI colour and remains disabled. Logs(open $TMPDIR) appear to show a socket related issue plus an internal 500, amongst other things. Please rename from .png to .zip

This Mojave 10.14.3 and integrated firewall is disabled btw, with no AV/Malware engine installed.

Thanks

[Brandon Smith]

I am having the exact same issue.

[Diego]

Same issue here, logs bellow:

NOTE: In my case, system proxy configurations are defined with a .pac file.

[2019-02-27 15:13:39:866] [info] Initializing splash screen.
[2019-02-27 15:13:39:910] [info] Attempting to run server - 5 attempts left.
[2019-02-27 15:13:39:910] [info] Generating random port.
[2019-02-27 15:13:39:910] [info] Trying to start server at port [33887].
[2019-02-27 15:13:40:450] [info] Displaying splash screen.
[2019-02-27 15:13:41:865] [info] Fetching .NET Core server status.
[2019-02-27 15:13:42:362] [info] Application successfully connected to .NET Core server [33887].
[2019-02-27 15:13:42:362] [info] Loading application in window.
[2019-02-27 15:13:42:365] [info] Maximizing application window.
[2019-02-27 15:13:42:481] [info] AutoUpdate is enabled.
[2019-02-27 15:13:42:517] [info] Checking for update
[2019-02-27 15:13:42:952] [info] Destroying splash screen.
[2019-02-27 15:13:43:793] [info] Update for version 0.2.2 is not available (latest version: 0.2.2, downgrade is disallowed).
[2019-02-27 15:13:42:011] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Specified argument was out of the range of valid values.
Parameter name: i
[2019-02-27 15:13:42:013] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-02-27 15:13:42:018] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-02-27 15:14:29:635] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Specified argument was out of the range of valid values.
Parameter name: i
[2019-02-27 15:14:29:635] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-02-27 15:14:29:635] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-02-27 15:14:29:659] [Error] [Angular] Failed to toggle capturing

 

[Dimitar]

Hi Diego,

For the moment,  we are not supporting Proxy Auto Configuration file handling on Mac and Linux. The full proxy configuration capabilities for Mac and Linux will come at a later stage of the development of Fiddler Everywhere.

Regards,
Dimitar
Progress Telerik

[Simeon]

Hi all,

Thank you for the feedback. It really helps us to improve Fiddler Everywhere.

Based on the stack traces from the logs, it seems that during application startup Fiddler Everywhere is unable to load its root CA certificate for HTTPS traffic from ~/.fiddler/Certificates/RootCertificate.p12 Unfortunately, this case is not handled appropriately in the current version and the rest of the startup logic is not executed. Hence, the proxy settings are not initialized and the Capture button does nothing.

Until, we fix this behavior in the next version, could you please, uncheck the 'Decrypt HTTPS traffic' setting, remove the ~/.fiddler/Certificates/RootCertificate.p12 certificate, then re-check the 'Decrypt HTTPS traffic' and trust the new certificate. This should make Fiddler Everywhere generate a new ~/.fiddler/Certificates/RootCertificate.p12 file which should be valid.

Thanks and Regards,
Simeon
Progress Telerik

[Rainier]

Hi Simeon, that seems to work, thanks!

[Simeon]

Hi Rainier, could you please, confirm that you are able to close Fiddler Everywhere and open it again and it starts to capture when you enter your password. Thanks!

Regards,
Simeon
Progress Telerik

[Rainier]

Indeed it does, which is surprising as I'm pretty sure I went through this a few times before but no dice. I don't recall seeing the authN prompts last time however. One other thing to mention - I actually updated it to the current version when the notification popped up, so maybe that's a factor.

If not then perhaps a transient issue with the OS and nowt to do with Fiddler, not sure, but it def works now having closed Fiddler and re-opened several times. I've actually opened a new thread on this :) https://www.telerik.com/forums/admin-password-required

Thanks

[An]

I'm still getting this error when closing the app after I delete the cert and reinstall the cert. This all happened when I started to use Charles and after I used Charles, I can't open FiddlerEverywhere anymore to get traffic. Before I was able to get traffic on my localhost without decrypt http and now I can't do that even when I reopen the app or reinstall the app. Can you take a look? Thanks.
Uncaught Exception:
Error: connect ECONNREFUSED 127.0.0.1:52776
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1161:14)

[Simeon]

Hi An,

Thanks for the feedback and sorry for the inconvenience. Could you please, provide us with the contents of your "$TMPDIR/Progress Telerik Fiddler/Logs" directory. I hope that it would allow us to investigate further the root cause of the problem.

Thanks and Regards,
Simeon
Progress Telerik

[An]

Sorry issue is resolved now. A reboot of my Mac re-prompted for my password and resolved the problem. I didn't need to install the security certificates nor check decrypt https. It works now after removing the certificates and rebooting my Mac. Thanks.

[Eleanor]

I did the steps above to turn off https decryption, then to export a new certificate to trust. Still no response when I click "Capture" button. Never seen a prompt for a password either. So... Fiddler Everywhere on macOS Mojave just isn't working at all for me. v 0.4.0

[Simeon]

Hi Eleanor, the second step regarding the certificate file deletion is very important. Here are the workaround instructions for your convenience:

1. uncheck the 'Decrypt HTTPS traffic' setting
2. delete the ~/.fiddler/Certificates/RootCertificate.p12 certificate
3. re-check the 'Decrypt HTTPS traffic'
4. trust the new certificate.

Regards,
Simeon
Progress Telerik

[Eleanor]

I've done all those steps several times. Cleaned out my keychain before 'trusting' the newly created certificate. Restarted the Mac. No auth prompt. No action on clicking 'Capture'

[Simeon]

Thanks for the confirmation. In this case, could you, please, provide me with the $TMPDIR/Progress Telerik Fiddler/Logs directory contents. It could help me find the root cause of the problem and to fix it.

Regards,
Simeon
Progress Telerik

[Eleanor]

Don't seem to have that path: 

$ cd $TMPDIR/Progress Telerik Fiddler/Logs
-bash: cd: /var/folders/g5/bnwx46md7tg_x0g8lyd0f_bjwnfqlm/T//Progress: No such file or directory

Could you give another way to find your logs?

[Simeon]

You should try with double quotes due the spaces in the path.
cd "$TMPDIR/Progress Telerik Fiddler/Logs"

Thanks,
Simeon
Progress Telerik

[Eleanor]

Well... having a hard time getting to that path using Mac's file upload dialog!

[Eleanor]

Copied them elsewhere... here are most recent logs

[Eleanor]

You only allow jpg etc... not log files in your attach function. So I had to take screenshots.

[Simeon]

Thanks Eleanor, you are great and providing me with the logs was really helpful. I would like to apologize for the inconvenience which this caused to you.

From the logs which I am seeing, Fiddler is having trouble getting the proxy server settings for the 'OSX Default' network connection.

I have two questions:

Is this your primary Internet connection?

What are the proxy server settings on the 'OSX Default' connection?

You can check you settings from System Preferences / Network, select the 'OSX Default' connection, click the Advanced... button and go to the Proxies tab.

If you are using the Auto Proxy Discovery or the Automatic Proxy Configuration options, they are still not supported for Mac and Linux.

If you would like, you could vote for this feature in our feedback portal.

Regards,
Simeon
Progress Telerik

[Eleanor]

Well, we are using Kensington Hubs and I'm attaching what's in the proxy tab on that connection (there is no OSX Default in my list). Don't know a heck of a lot about proxy settings. My company does not use proxies. I do notice the "bypass for these hosts and domains" listing... for what it's worth.

[Mario]

I've been looking at the feedback and trying the different steps that are available and nothing is working. Here is my log file. Could I please get some assistance? Here are a few things that are (not) happening:
1. Not getting a request for a username/password
2. Capture isn't working at all
3. I use a VPN...although it's currently not on. Will that give me any trouble?

[Mario]

Attached file.

[Alon]

Hi,

I'm having the same problem when trying to use the application to proxy my network traffic.

1. When clicking on the 'Capture' button nothing happens.

2. I tried to uncheck+delete+re-check process and I didn't get the 'trust new certificate' popup and this didn't help in solving the issue.

3. Attached the logs from the "$TMPDIR/Progress Telerik Fiddler/Logs" folder.

4. I don't have any 'fiddler' cert in my keyChain - See attached image.

Can you please assist me?

 

Thanks,

Alon.

[Eric R | Senior Technical Support Engineer]

Hi Alon,

From the logs it looks like Fiddler Everywhere is opening and closing fine but this may be an issue with .NET Core. Before we start investigating .NET Core, can you answer the following questions:

1. - When you open Fiddler Everywhere and check the Proxy settings for the default Network are the Web Proxy (HTTP) and Secure Web Proxy (HTTPS) checkboxes selected?

2. - Is .NET Core installed?

3. - What version of macOS is being used?

Please let me know if you need any additional information. Thank you and I look forward to your reply.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Mario]

Hi Eric R,

I post for help but didn't hear anything back. But here are the answers to your questions.

 

1. Nothing is selected as far as Proxy Settings in the Network Settings area.

2. Yes, .NET Core is installed. I'm on version 2.2.105

3. The version of Mac I'm on is Mojave 10.14.6

 

I hope this helps.

[Eleanor]

Hey, I'm not Alon, but I looked at default Network and the Web Proxy (HTTP) and Secure Web Proxy (HTTPS) checkboxes were not selected. I selected them, and when I opened Fiddler Everywhere, I was prompted for proxy password (used my registered fingerprint to allow), and the capture button started working (it prompted for proxy pw again first).

[Eleanor]

Oh, and it would be nice if the documentation mentioned those settings were needed, even though they're not Fiddler settings!

[Eric R | Senior Technical Support Engineer]

Hi Everyone,

I tested this on macOS Mojave version 10.14.6. I opened up Fiddler Everywhere and verified the Web Proxy and Secure Web Proxy settings were checked. This happened automatically on start when I tested it.

If this is not happening automatically when Fiddler Everywhere is opened, it is likely this setting has been unchecked. I recommend ensuring the Act as system proxy on startup is checked in the Fiddler Everywhere Settings. See the below screenshot for more details.



If the issue persists, as a workaround, manually set the Web Proxy and Secure Web Proxy in macOS settings. System Preferences -> Network -> Advanced

Please let me know if you need any additional information. Thank you.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Alon]

Hi Eric,
Thank you for the response.
1- Both checkboxes are NOT marked on both of my working network connections
2- I wasn't sure so I install it anyway again.
3- Mac OS: 10.14.6

After installing the .Net Core I tried to open the 'Fiddler Everywhere' application again and I got an update popup to version 0.50.
I installed it also and it still doesn't work.
When I verified the latest workaround you suggested and set the Web Proxy (HTTP) and Secure Web Proxy (HTTPS) checkboxes manually with the 8866 port and Fiddler automatically started to capture the traffic.
I can just indicate 2 issues after this was solved:
1. The 'Capture' button is still not responding.
2. The proxy checkboxes are not checked automatically when launching 'Fiddler'.

Thank you for all of your assistance.
Alon.

[Dark]

Glenn,

I had the same issues as what you are encountering.  What finally solved it for me was to perform the following steps:

1. Open Fiddler Everywhere and disable the HTTPS setting (Uncheck the Decrypt HTTPS traffic in the HTTPS settings page)
2. Close Fiddler
3. Open your Mac user home directory (~) and delete the .fiddler (hidden) folder
4. Open the advanced settings for the active network connection in the OS settings:
   1. System Preferences
   2. Network
   3. Select active network, then hit the Advanced button, open the Proxies tab
5. Ensure the Web Proxy (HTTP) and the Secure Web Proxy (HTTPS) setting is checked and specify 127.0.0.1 for the web proxy server and 8866 for the port.  Close out of the OS settings.
6. Open Fiddler, and hopefully you will get prompted for your password.

If you don't get the password prompt, you might need to disable additional settings within Fiddler (example: Act as system proxy on startup) and then perform the steps above again before re-enabling the settings.

 

NOTE: It seems as though Fiddler will start having issues when I log into a VPN (I'm using the Cisco AnyConnect software to remote into our work network).  And then it will start to have the above noted issues.  Also, it WILL NOT work if a VPN connection is active.  Is there any way to correct these issues? 

 

Thanks

[Glenn]

I'm having the same difficulties.  MacOS 10.14.6, running Fiddler 0.5.0.

I tried installing mono ("brew install mono"), .NET ("brew cask install dotnet"), and then tried both Fiddler for OSX and Fiddler Everywhere.  Fidder for Mac never worked (too many mono errors), and while Fiddler Everywhere installed correctly, it never will capture anything.  Clicking on "Capture" does nothing, the button doesn't even appear to click / engage / change-color.

Tried everything above, including rebooting my mac, reinstalling Fiddler, clearing out the certificate, etc.  Nothing works.

[Glenn]

BTW, here's what I get if I run from within a terminal, as sudo:

gstrycker@chi-gstryck-mac:~$ sudo /Applications/Progress\ Telerik\ Fiddler.app/Contents/MacOS/Progress\ Telerik\ Fiddler
16:34:55.424 › [Product information] Progress Telerik Fiddler 0.5.0
16:34:55.440 › [System information] Darwin chi-gstryck-mac 18.7.0 Darwin Kernel Version 18.7.0: Tue Aug 20 16:57:14 PDT 2019; root:xnu-4903.271.2~2/RELEASE_X86_64 x86_64
16:34:55.497 › Initializing splash screen.
2019-10-15 16:34:55.567 Progress Telerik Fiddler[5369:218466] *** WARNING: Textured window <AtomNSWindow: 0x7fd1cdc852f0> is getting an implicitly transparent titlebar. This will break when linking against newer SDKs. Use NSWindow's -titlebarAppearsTransparent=YES instead.
16:34:55.591 › Attempting to run server - 5 attempts left.
16:34:55.592 › Generating random port.
16:34:55.592 › Trying to start server at port [34835].
16:34:57.945 › Fetching .NET Core server status.
16:34:58.488 › Application successfully connected to .NET Core server [34835].
16:34:58.489 › Loading application in window.
16:34:58.517 › Maximizing application window.
16:34:58.625 › AutoUpdate is enabled.
16:34:58.626 › Checking for update
16:34:59.112 › Destroying splash screen.
16:34:59.285 › Update for version 0.5.0 is not available (latest version: 0.5.0, downgrade is disallowed).
16:35:20.012 › Closing server...
16:35:26.123 › Server successfully closed.
16:35:26.124 › Application exited with code 0.

 

[Eric R | Senior Technical Support Engineer]

Hi Glenn,

Thank you for providing the terminal output. Although, there isn't any indication of an error from the output. Is it possible to provide a screen recording of the behavior you're experiencing? If so, I ask that you record the following actions.

1. Open Fiddler Everywhere

2. Click the Capture/Capturing button

3. Click the Settings Icon to open the Settings Dialog

4. Click the HTTPS Tab

5. Click the Connections Tab

6. Click the Gateway Tab

7. Close the Settings Dialog

8. Hover over the Network Tab

10. Open a terminal and run dotnet --info

Once I have the above information, I will be able to provide a better response.

Please let me know if this is possible. Thank you and I look forward to your reply.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Glenn]

I tried making a quicktime movie, but it's always above 2MB and the site won't let me update it.  Send me a personal email to glenn dot strycker at g-mail and I can send you the file.

I'll try to attach screenshots here.  Note that I've tried other combinations for the settings as others have suggested on the thread, and all give the same conclusion (the "Capture" button will not click / change color / do anything).

Also note that I tried several ports.... 8866 was the default I believe, I tried 8888 since that was what "Charles" uses and I got that to work, and I also tried 8060, too.  All of these resulted in the same behavior.

 

[Glenn]

Try this link for the video:

https://drive.google.com/open?id=1BwTx4Z2B3EuFzRWJdgCcpeKUo7EWzi09

[Eric R | Senior Technical Support Engineer]

Hi Glenn,

Thank you for the video. This was very helpful. I recommend selecting the Use system proxy (recommended) Radio Button in the Gateway settings. See the below screenshot for a visual reference.

Please give this a try and let me know the results. Thank you and I look forward to your reply.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Glenn]

Tried that - no change.

I think I've attempted most of the possible combinations for these check boxes and radio buttons.  Any particular ports I should try?

[Eric R | Senior Technical Support Engineer]

Hi Glenn,

In that case, it might be helpful to reset everything to default and restarting Fiddler Everywhere. After restarting Fiddler Everywhere, confirm the System Proxy Settings on the Machine by ensuring the Web Proxy (HTTP) and Secure Web Proxy (HTTPS) CheckBoxes are checked.

See below for the default settings for Fiddler Everywhere and the System Proxy Settings for the Machine.

Fiddler Everywhere

Mac proxies Settings

Please give this a try and let me know the results. Thank you.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Stephan]

Hi.. I have the same issue where capture button does not do anything. Tried to re trust certificate as described.

 

log:

[2019-10-30 15:47:08:342] [info] [Product information] Progress Telerik Fiddler 0.5.0
[2019-10-30 15:47:08:350] [info] [System information] Darwin bea-x1b.webdanmark.local 19.0.0 Darwin Kernel Version 19.0.0: Wed Sep 25 20:18:50 PDT 2019; root:xnu-6153.$
[2019-10-30 15:47:08:474] [info] Initializing splash screen.
[2019-10-30 15:47:08:523] [info] Attempting to run server - 5 attempts left.
[2019-10-30 15:47:08:523] [info] Generating random port.
[2019-10-30 15:47:08:523] [info] Trying to start server at port [9362].
[2019-10-30 15:47:10:794] [info] Fetching .NET Core server status.
[2019-10-30 15:47:11:228] [info] Application successfully connected to .NET Core server [9362].
[2019-10-30 15:47:11:228] [info] Loading application in window.
[2019-10-30 15:47:11:250] [info] Maximizing application window.
[2019-10-30 15:47:11:357] [info] AutoUpdate is enabled.
[2019-10-30 15:47:11:358] [info] Checking for update
[2019-10-30 15:47:11:686] [info] Destroying splash screen.
[2019-10-30 15:47:11:962] [info] Update for version 0.5.0 is not available (latest version: 0.5.0, downgrade is disallowed).
[2019-10-30 15:52:16:487] [info] Closing server...
[2019-10-30 15:52:22:600] [info] Server successfully closed.
[2019-10-30 15:52:22:601] [info] Application exited with code 0.

netcore:

[2019-10-30 15:47:10:940] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:47:10:942] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:47:10:946] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:49:40:868] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:49:40:868] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:49:40:868] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:49:40:881] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:49:49:593] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:49:49:593] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:49:49:593] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:49:49:596] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:49:50:417] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:49:50:417] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:49:50:417] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:49:50:420] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:49:59:766] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:49:59:766] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:49:59:766] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:49:59:769] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:50:00:123] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:50:00:123] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:50:00:123] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:50:00:126] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:50:00:273] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:50:00:273] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:50:00:273] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:50:00:276] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:50:00:446] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:50:00:446] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:50:00:446] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:50:00:448] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:50:00:608] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:50:00:608] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:50:00:608] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2019-10-30 15:50:00:610] [Error] [Angular] Failed to toggle capturing
[2019-10-30 15:50:00:777] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Spec$
Parameter name: i
[2019-10-30 15:50:00:777] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2019-10-30 15:50:00:777] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.

 

[Eric R | Senior Technical Support Engineer]

Hi Stephan,

This appears to be something blocking Fiddler Everywhere from Registering as the System Proxy. I recommend opening up Fiddler Everywhere and then verifying the Proxy Settings a configured. See the below screenshots for what the Proxy Settings should be like when Fiddler Everywhere is running and not.

Fiddler Everywhere Not Running

Mac Proxy Settings when Fiddler Everywhere is not running.

Fiddler Everywhere Running

Mac proxy settings when Fiddler Everywhere is running.

If the above behavior is not working as expected, I recommend checking the Web Proxy (HTTP) and Secure Web Proxy (HTTPS) items while Fiddler Everywhere is running and verifying that Capturing works.

Please give this a try and let me know the results. Thank you and I look forward to your reply.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Glenn]

Whenever I change my Mac proxy settings and click "ok" and then "apply" in the Network dialog box, nothing happens, and when I go back into the Mac proxy settings the checkboxes are unmarked.

This may be a Mac error and not Fiddler per se, but I cannot seem to get my Mac proxy changes to apply and persist.  Any ideas?

[Glenn]

I think this is my issue here:  https://apple.stackexchange.com/questions/106742/mac-username-password-for-proxy-settings-keep-resetting-by-itself

There may be a solution on this article, too, and it involves the system keychain instead of the user keychain.

[Glenn]

One last observation... my Mac proxy settings dialog box looks different than Eric's screen capture above.  There are additional settings that I do not know how to fill.  What should be entered for the "proxy server" string fields?

[Glenn]

screen shot

[Eric R | Senior Technical Support Engineer]

Hi Glenn,

I agree this is probably associated with the Mac configuration for changing the Proxy Settings. When I tested this in a local Mac environment, I had to provide my credentials when I started and shutdown Fiddler Everywhere. Although, I am not sure what would configuration would be set in order to bypass this.

Additionally, this could be cause by an application as well which may be blocking any changes to the proxy. VPN and Firewall software commonly do this.

As for the settings, the Auto Proxy Discovery is is usually for providing a .PAC file to configure the Proxy via a script. If you're not using that you can uncheck it.

Please let me know if you need any additional information. Thank you.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Glenn]

@Dark, thank you, that totally worked!  Actually I wasn't even prompted for a password, the issue was that System Preferences / Network / Proxy / checkboxes wouldn't set and save without having the address and port specified.  Once I added those, I was able to save the preferences and apply them, so when I opened Fiddler it worked as expected.

[Eric R | Senior Technical Support Engineer]

Hi Everyone,

After reviewing more thoroughly, we have a Feedback Request Item for not seeing any records on a Mac. It appears that this might also have to do with using an Ethernet and a WiFi adapter. We are currently investigating different approaches for persisting System Proxy Settings on Mac.

As a workaround, I recommend following the steps outlined by @Dark below.

1. Open Fiddler Everywhere and disable the HTTPS setting (Uncheck the Decrypt HTTPS traffic in the HTTPS settings page)
2. Close Fiddler
3. Open your Mac user home directory (~) and delete the .fiddler (hidden) folder
4. Open the advanced settings for the active network connection in the OS settings:
   1. System Preferences
   2. Network
   3. Select active network, then hit the Advanced button, open the Proxies tab
5. Ensure the Web Proxy (HTTP) and the Secure Web Proxy (HTTPS) setting is checked and specify 127.0.0.1 for the web proxy server and 8866 for the port.  Close out of the OS settings.
6. Open Fiddler, and hopefully you will get prompted for your password.
   

As a token of gratitude for everyone's feedback, I have added a vote for each of you on this thread and encourage following to receive status updates. 

Please stay tuned for any additional information in the Feedback Request. Thank you again for your patience and for using the Fiddler Forums.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Dark]

Glad the workaround resolved the issue you were encountering.  I just felt the need to document it in case others needed the same solution.

[Dark]

Eric,

I also did previously notice that I had issues when trying to connect to the network using the Thunderbolt Ethernet Adapter, so I just stuck to using Wifi instead since that did not suffer from the same issue of not showing requests in Fiddler.

 

Is there any way to be able to use Fiddler Everywhere while connected to a VPN server?  Do you know if this is a bug/feature request that might be on the roadmap for the future?

Thanks

[Eric R | Senior Technical Support Engineer]

Hi Dark,

Thank you for your feedback. I will add the notes about the Thunderbolt Ethernet Adapter to our backlog.

As far as the VPN, Fiddler Everywhere should work when using default settings. Although, we are currently investigating use cases with VPN on Mac computers. I encourage following the Feedback Request Item to receive future updates.

Please let me know if you need any additional information. Thank you.

Regards,

Eric R | Technical Support Engineer
Progress Telerik

[Dirk]

Fiddler was one of my primary debugging tools when working in Windows environment.  Having recently moved to Mac I was excited to see Everywhere as an option.  I was able to get it running (the instructions really are not clear and could be improved).  I had to manually enable proxies and then Fiddler started capturing EVERYTHING, without even clicking CAPTURE.  I went to look for the Filters that I was accustomed to in the Windows version, but it doesn't appear that they are supported yet?  Without them, Everywhere is not very useful for me.  Do you have a roadmap for the full feature set compatible with Windows (especially scripting)?  I hope so as a full port would be extremely helpful to my day-to-day development!   

[Eric R | Senior Technical Support Engineer]

Hi Dirk,

We are glad to hear that you enjoy using Fiddler and understand the desire for feature set compatibility between Fiddler Desktop and Fiddler Everywhere. Rest assured we are working diligently to achieve feature parity.

At this time, the best sources for feature status is the Fiddler Everywhere Feedback Portal and the What's New section of the home page. I encourage reviewing the items in the feedback portal, voting for them and following them for additional updates. Let me provide the direct link to the referenced feature below.

Add Filtering Options for Capturing Traffic for MacOS

Additionally, we are always looking for users to provide additional feedback and welcome you to become a Fiddler Insider.

As always, thank you for your feedback and let me know if you need any additional information.

Regards,

Eric R | Senior Technical Support Engineer
Progress Telerik

[Ferdinand]

Hi Eric,

I tried Fiddler Everywhere 0.5.0 and I can confirm the same problem as posted here last year. Capturing does not work. Enabling the system proxy fails.

1. No, they are not.
2. Yes, it is. Installed by `brew install dotnet` for other purposes. But your documentation does not mention it.
3. Mojave 10.14.6.

It appears that Fiddler nether registers itself as a system proxy (with 127.0.0:8866 in Network Settings), nor it starts a server listening on the port 8866 (checked by netstat).

netcore.log:

[2020-05-24 15:25:27:851] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Specified argument was out of the range of valid values.
Parameter name: i
[2020-05-24 15:25:27:853] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2020-05-24 15:25:38:822] [Information] [Fiddler] !WARNING: Failed to get proxy information for Connection 'OSX Default' due to System.ArgumentOutOfRangeException Specified argument was out of the range of valid values.
Parameter name: i
[2020-05-24 15:25:38:822] [Information] [Fiddler] !WARNING: The Default Gateway information could not be obtained.
[2020-05-24 15:25:38:824] [Information] [Fiddler] Error: Failed to register Fiddler as the system proxy.
[2020-05-24 15:25:38:858] [Error] [Angular] Failed to toggle capturing
[2020-05-24 15:27:00:236] [Error] [NETCore] The remote party closed the WebSocket connection without completing the close handshake.
System.Net.WebSockets.WebSocketException (0x80004005): The remote party closed the WebSocket connection without completing the close handshake. ---> System.Threading.Tasks.TaskCanceledException: The request was aborted ---> Microsoft.AspNetCor
e.Server.Kestrel.Transport.Abstractions.Internal.ConnectionAbortedException: The
connection was aborted
   at Microsoft.AspNetCore.Server.Kestrel.Internal.System.IO.Pipelines.PipeComple
tion.ThrowFailed()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.System.IO.Pipelines.Pipe.GetResult(ReadResult& result)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.System.IO.Pipelines.Pipe.Microsoft.AspNetCore.Server.Kestrel.Internal.System.IO.Pipelines.IReadableBufferAwaiter.GetResult()
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.MessageBody.ReadAsync(ArraySegment`1 buffer, CancellationToken cancellationToken)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.FrameRequestStream.ReadAsyncInternal(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.FrameRequestStream.ReadAsyncInternal(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   at System.Net.WebSockets.ManagedWebSocket.EnsureBufferContainsAsync(Int32 minimumRequiredBytes, CancellationToken cancellationToken, Boolean throwOnPrematureClosure)
   at System.Net.WebSockets.ManagedWebSocket.ReceiveAsyncPrivate(ArraySegment`1 payloadBuffer, CancellationToken cancellationToken)
      at System.Net.WebSockets.ManagedWebSocket.ReceiveAsyncPrivate(ArraySegment`1 payloadBuffer, CancellationToken cancellationToken)
      at Fiddler.WebUi.Services.WebSockets.WebSocketWrapper.ReceiveAsync() in /Users/jenkins/workspace/WebUI_Mac/Fiddler/WebUi/Fiddler.WebUi/Services/WebSockets/WebSocketWrapper.cs:line 60

[Nick Iliev]

Hello Ferdinand,

 

The Fiddler Everywhere team is, as we speak, working on a new version that will provide improved MAC workflow for setting Fiddler as a proxy and for enabling HTTPS capturing. The new version is expected within days and once published will be available from the download page.

Once again -  Thank you for being a valued Fiddler Everywhere user!

 

Regards,
Nick Iliev
Progress Telerik