Cannot run Fiddler on WIndows 10

[Jim]

Double clicked the icon and nothing happens. (Be handy if you popped up a message about why the program is not running.) I found the .exe and ran it from a command line. This is the output.

 

09:42:25.911 > [Product information] Fiddler Everywhere 1.5.1
09:42:25.925 > [System information] win32 (Windows_NT/x64) - version 10.0.19041
09:42:25.967 > Initializing splash screen.
09:42:25.981 > Attempting to run server - 5 attempts left.
09:42:25.993 > Calculating the URL of ASP.NET Server application.
09:42:26.005 > Generating random port.
09:42:26.017 > Trying to start server at port [47329].
09:42:29.032 > Application did not receive required message for 3000ms.
09:42:29.045 > Fetching .NET Core server status.
09:42:31.071 > Error occurred while fetching .NET Core server [47329] status. Error message: connect ECONNREFUSED 127.0.0.1:47329
09:42:31.084 > Attempting to run server - 4 attempts left.
09:42:31.096 > Calculating the URL of ASP.NET Server application.
09:42:31.108 > Generating random port.
09:42:31.120 > Trying to start server at port [28688].
09:42:31.134 > Unable to start server process, closed with code: null
09:42:31.147 > Fetching .NET Core server status.
09:42:33.162 > Error occurred while fetching .NET Core server [28688] status. Error message: connect ECONNREFUSED 127.0.0.1:28688
09:42:37.132 > Application did not receive required message for 6000ms.
09:42:37.145 > Fetching .NET Core server status.
09:42:39.160 > Error occurred while fetching .NET Core server [28688] status. Error message: connect ECONNREFUSED 127.0.0.1:28688
09:42:39.181 > Attempting to run server - 3 attempts left.
09:42:39.193 > Calculating the URL of ASP.NET Server application.
09:42:39.204 > Generating random port.
09:42:39.215 > Trying to start server at port [3687].
09:42:39.230 > Unable to start server process, closed with code: null
09:42:39.243 > Fetching .NET Core server status.
09:42:41.258 > Error occurred while fetching .NET Core server [3687] status. Error message: connect ECONNREFUSED 127.0.0.1:3687

[Nick Iliev]

Hello Jim,

 

Fiddler Everywhere requires a connection with access to the Internet (and specifically to the endpoint described here). From the provided logs, it appears that your system uses a proxy, which prevents the fetching of the required NET core server status.

If possible, try to remove the pre-set OS proxy and reconnect Fiddler Everywhere. On Windows, that would mean removing the proxy from Start > Proxy Settings > Manual proxy setup.

 

Regards,
Nick Iliev
Progress Telerik

[Jim]

I do not have a manual proxy. But the Automatic Detect Proxy box was checked so I turned that off too. It made no difference.

[Nick Iliev]

Hello Jim,

 

Could you verify that you have an active connection to the internet (and access to the addresses listed here)? Also if possible please send us the FIddler log files (refer to this article).

As a side note, as you are using Fiddler Everywhere, you could checkthe Fiddler Everywhere forum for possible solutions to problems similar to yours.

 

Regards,
Nick Iliev
Progress Telerik

[Jim]

I have an active connection - it is the same computer I am communicating with you on this forum. I have tried to access the four addresses you mention - I could ping two of them but the other two did not respond to ping.

I turned off my Windows Firewall and went into Advanced settings to ensure I allowed Fiddler Everywhere output port access. None of this made any difference.

The error logs were empty but here is the output when I run the program in a command window.

 

09:54:04.193 > Maximum number of attempts reached - quitting application.
09:54:04.208 > Unable to start the server, error is Maximum number of attempts reached - quitting application.
09:54:04.222 > [CPU information] The processor model is: Intel(R) Core(TM) i7-8086K CPU @ 4.00GHz with number of cores: 12 and working at 4.008 GHz frequency
09:54:04.236 > [Memory information] The total amount of memory is 16333.47265625 MBs.
(electron) The default value of app.allowRendererProcessReuse is deprecated, it is currently "false".  It will change to be "true" in Electron 9.  For more information please check https://github.com/electron/electron/issues/18397
09:54:04.302 > Unable to start server process, closed with code: null
09:54:04.319 > Fetching .NET Core server status.
[2021-02-23T15:54:04.350Z] Warning: Error from HTTP request. Error: connect ECANCELED 127.0.0.1:47777
[2021-02-23T15:54:04.350Z] Error: Failed to complete negotiation with the server: Error: connect ECANCELED 127.0.0.1:47777
[2021-02-23T15:54:04.351Z] Error: Failed to start the connection: Error: connect ECANCELED 127.0.0.1:47777
09:54:04.351 > {
  constructor: 'Error',
  errno: 'ECANCELED',
  code: 'ECANCELED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 47777,
  stack: 'Error: connect ECANCELED 127.0.0.1:47777\n' +
    '    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1128:14)'
}
(node:23384) UnhandledPromiseRejectionWarning: Error: Object has been destroyed
    at BrowserWindowService.<anonymous> (C:\Users\jimth\AppData\Local\Programs\Fiddler Everywhere\resources\app\out\services\windows\browser-window-service.js:107:35)
    at Generator.throw (<anonymous>)
    at rejected (C:\Users\jimth\AppData\Local\Programs\Fiddler Everywhere\resources\app\out\services\windows\browser-window-service.js:5:65)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
(node:23384) UnhandledPromiseRejectionWarning: Error: Object has been destroyed
    at BrowserWindowService.<anonymous> (C:\Users\jimth\AppData\Local\Programs\Fiddler Everywhere\resources\app\out\services\windows\browser-window-service.js:107:35)
    at Generator.throw (<anonymous>)
    at rejected (C:\Users\jimth\AppData\Local\Programs\Fiddler Everywhere\resources\app\out\services\windows\browser-window-service.js:5:65)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
(node:23384) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 4)
(node:23384) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 4)
(node:23384) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
(node:23384) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
[2021-02-23T15:54:04.372Z] Warning: Error from HTTP request. Error: connect ECANCELED 127.0.0.1:47777
[2021-02-23T15:54:04.372Z] Error: Failed to complete negotiation with the server: Error: connect ECANCELED 127.0.0.1:47777
[2021-02-23T15:54:04.372Z] Error: Failed to start the connection: Error: connect ECANCELED 127.0.0.1:47777
09:54:04.372 > {
  constructor: 'Error',
  errno: 'ECANCELED',
  code: 'ECANCELED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 47777,
  stack: 'Error: connect ECANCELED 127.0.0.1:47777\n' +
    '    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1128:14)'
}
09:54:04.387 > Error occurred while fetching .NET Core server [47777] status. Error message: connect ECANCELED 127.0.0.1:47777

[Nick Iliev]

Hey Jim,

 

The logs are indicating that your OS is still using another proxy. Apart from verifying that there are no manual proxy settings in the  Proxy Settings screen, could you please also verify the following:

- Open the Windows 10 Proxy settings screen and once again turn off "Automatically detect settings" and "Use script setup" switches. If your system is using a proxy script (from the "Use script setup") and you can remove it, then make sure to remove the loopback address proxying from the automatic proxy script.

- Go to another settings page and return to the Windows 10 Proxy settings screen. Check if the settings are still disabled (we had previously observed cases where 3rd-party apps or administrative restrictions turn those back on).

- Check if your system uses global environment variables HTTP_PROXY and HTTPS_PROXY and unset those if they are set to a different proxy.

 

 

Regards,
Nick Iliev
Progress Telerik

[Jim]

All Proxy settings were turned off and continue to be; there is no proxy script. There are no environment variables for HTTP_PROXY or HTTPS_PROXY.

I have a thought. I have a business account with my ISP provider which provides me with 5 static IP addresses. One of those static IPs is used to access the internet on this Windows 10 computer. Could the fact that I am using a static IP, rather than dynamic IP, be an issue? (Even though my ISP knows me by a static IP my router dishes out numerous dynamic IPs to the devices on the network, such as printers, credit card readers, even this computer which is 192.168.0.117, etc. )

 

[Nick Iliev]

Hello Jim,

 

For Fiddler Everywhere there is no difference between a static and a dynamic IP so that is highly unlikely the reason for your issue. Could please do the following so we could continue the investigation:

- Manually open the folder that contains the FIddler error logs. At Windows 10 that would be the following:

%APPDATA%\Fiddler Everywhere\Logs

- Delete all files inside.

- Start the FIddler Everywhere application.

- Send us the newly generated Fiddler Everywhere log files.

 

Regards,
Nick Iliev
Progress Telerik

[Jim]

Here is the electron.log

[2021-02-25 08:05:07:829] [info] [Product information] Fiddler Everywhere 1.5.1
[2021-02-25 08:05:07:835] [info] [System information] win32 (Windows_NT/x64) - version 10.0.19041
[2021-02-25 08:05:07:870] [info] Initializing splash screen.
[2021-02-25 08:05:07:875] [info] Attempting to run server - 5 attempts left.
[2021-02-25 08:05:07:879] [info] Calculating the URL of ASP.NET Server application.
[2021-02-25 08:05:07:883] [info] Generating random port.
[2021-02-25 08:05:07:887] [info] Trying to start server at port [51365].
[2021-02-25 08:05:10:898] [error] Application did not receive required message for 3000ms.
[2021-02-25 08:05:10:903] [info] Fetching .NET Core server status.
[2021-02-25 08:05:12:927] [error] Error occurred while fetching .NET Core server [51365] status. Error message: connect ECONNREFUSED 127.0.0.1:51365
[2021-02-25 08:05:12:935] [info] Attempting to run server - 4 attempts left.
[2021-02-25 08:05:12:939] [info] Calculating the URL of ASP.NET Server application.
[2021-02-25 08:05:12:942] [info] Generating random port.
[2021-02-25 08:05:12:946] [info] Trying to start server at port [13134].
[2021-02-25 08:05:12:954] [info] Unable to start server process, closed with code: null
[2021-02-25 08:05:12:959] [info] Fetching .NET Core server status.
[2021-02-25 08:05:14:968] [error] Error occurred while fetching .NET Core server [13134] status. Error message: connect ECONNREFUSED 127.0.0.1:13134
[2021-02-25 08:05:18:953] [error] Application did not receive required message for 6000ms.
[2021-02-25 08:05:18:962] [info] Fetching .NET Core server status.
[2021-02-25 08:05:20:971] [error] Error occurred while fetching .NET Core server [13134] status. Error message: connect ECONNREFUSED 127.0.0.1:13134
[2021-02-25 08:05:20:981] [info] Attempting to run server - 3 attempts left.
[2021-02-25 08:05:20:985] [info] Calculating the URL of ASP.NET Server application.
[2021-02-25 08:05:20:988] [info] Generating random port.
[2021-02-25 08:05:20:992] [info] Trying to start server at port [31007].
[2021-02-25 08:05:20:999] [info] Unable to start server process, closed with code: null
[2021-02-25 08:05:21:003] [info] Fetching .NET Core server status.
[2021-02-25 08:05:23:012] [error] Error occurred while fetching .NET Core server [31007] status. Error message: connect ECONNREFUSED 127.0.0.1:31007
[2021-02-25 08:05:32:998] [error] Application did not receive required message for 12000ms.
[2021-02-25 08:05:33:008] [info] Fetching .NET Core server status.
[2021-02-25 08:05:35:014] [error] Error occurred while fetching .NET Core server [31007] status. Error message: connect ECONNREFUSED 127.0.0.1:31007
[2021-02-25 08:05:35:019] [info] Attempting to run server - 2 attempts left.
[2021-02-25 08:05:35:023] [info] Calculating the URL of ASP.NET Server application.
[2021-02-25 08:05:35:027] [info] Generating random port.
[2021-02-25 08:05:35:030] [info] Trying to start server at port [55590].
[2021-02-25 08:05:35:038] [info] Unable to start server process, closed with code: null
[2021-02-25 08:05:35:043] [info] Fetching .NET Core server status.
[2021-02-25 08:05:37:053] [error] Error occurred while fetching .NET Core server [55590] status. Error message: connect ECONNREFUSED 127.0.0.1:55590
[2021-02-25 08:05:59:038] [error] Application did not receive required message for 24000ms.
[2021-02-25 08:05:59:048] [info] Fetching .NET Core server status.
[2021-02-25 08:06:01:055] [error] Error occurred while fetching .NET Core server [55590] status. Error message: connect ECONNREFUSED 127.0.0.1:55590
[2021-02-25 08:06:01:065] [info] Attempting to run server - 1 attempts left.
[2021-02-25 08:06:01:069] [info] Calculating the URL of ASP.NET Server application.
[2021-02-25 08:06:01:073] [info] Generating random port.
[2021-02-25 08:06:01:077] [info] Trying to start server at port [30747].
[2021-02-25 08:06:01:085] [info] Unable to start server process, closed with code: null
[2021-02-25 08:06:01:097] [info] Fetching .NET Core server status.
[2021-02-25 08:06:03:105] [error] Error occurred while fetching .NET Core server [30747] status. Error message: connect ECONNREFUSED 127.0.0.1:30747
[2021-02-25 08:06:49:084] [error] Application did not receive required message for 48000ms.
[2021-02-25 08:06:49:098] [info] Fetching .NET Core server status.
[2021-02-25 08:06:51:114] [error] Error occurred while fetching .NET Core server [30747] status. Error message: connect ECONNREFUSED 127.0.0.1:30747
[2021-02-25 08:06:51:119] [error] Maximum number of attempts reached - quitting application.
[2021-02-25 08:06:51:123] [error] Unable to start the server, error is Maximum number of attempts reached - quitting application.
[2021-02-25 08:06:51:129] [info] [CPU information] The processor model is: Intel(R) Core(TM) i7-8086K CPU @ 4.00GHz with number of cores: 12 and working at 4.008 GHz frequency
[2021-02-25 08:06:51:133] [info] [Memory information] The total amount of memory is 16333.47265625 MBs.
[2021-02-25 08:06:51:215] [error] {
  constructor: 'Error',
  errno: 'ECANCELED',
  code: 'ECANCELED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 30747,
  stack: 'Error: connect ECANCELED 127.0.0.1:30747\n' +
    '    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1128:14)'
}
[2021-02-25 08:06:51:226] [error] {
  constructor: 'Error',
  errno: 'ECANCELED',
  code: 'ECANCELED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 30747,
  stack: 'Error: connect ECANCELED 127.0.0.1:30747\n' +
    '    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1128:14)'
}

[Nick Iliev]

Hey Jim,

 

Please try to execute the following command from your command prompt (Start > Run > cmd)

"%LOCALAPPDATA%\Programs\Fiddler Everywhere\resources\app\out\WebServer\Fiddler.WebUi.exe"

If the command is successfully executed, it should return something similar to the output below:

info: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[0]
      User profile is available. Using 'C:\Users\niliev\AppData\Local\ASP.NET\DataProtection-Keys' as key repository and Windows DPAPI to encrypt keys at rest.
Server ready
Hosting environment: Production
Content root path: D:\fd\fiddler-jam-docs
Now listening on: http://localhost:5000

If the command returns Server Ready (as in the sample output and you are still experiencing troubles that would mean the issue is related to proxy settings being used on your OS. In this case, look for a 3rd-party tool setting a proxy, for OS proxy settings that are leaked, or contact your administrator if the machine is not maintained by your directly.

However, If the above command returns an error send then please post it there so we could investigate the case further.

 

Regards,
Nick Iliev
Progress Telerik

[Jim]

Fiddler.WebUi.exe produced the expected output, namely, 'Server Ready'.

So I went through the list of installed programs and uninstalled two programs I never use and might conflict: Twitch and Wireshark. I also rebooted my computer. Fiddler is now working. While I suspect Wireshark I downloaded the 350 page documentation and can find no reference to Wireshark creating a proxy?? Wish there was a Windows utility that could show proxy servers as everything in the Control Panel said I was not using a proxy. Regardless, it seems your guidance was correct and you may close this ticket.

[Nick Iliev]

Hi Jim,

 

Glad to hear that you were able to resolve the issue!

I am also interested in why would Fiddler not work alongside Wireshark - could you please let us know if Fiddler can work together with Wireshark after the reboot and if the starting order is of essence (e.g., if it matters if FIddler is started before Wireshark or the opposite).

 

Regards,
Nick Iliev
Progress Telerik