Closing Fiddler Causes Internet Connect Loss

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7 posts, 0 answers
  1. Lisa
    Lisa avatar
    2 posts
    Member since:
    Nov 2019

    Posted 13 Nov 2019 Link to this post

    Hello.  I've got tons of experience using Fiddler but it was on my old Windows 7 machine a couple years ago.  I'm getting back to using Fiddler again, now on a Mac Book Pro, running Mojave.  When I close Fiddler, whether by clicking the close icon on the window or selecting Quit from the menu, it causes my internet to be unusable. I get proxy errors in the browsers.  I've followed directions to reset the proxies in system settings and this changes nothing.  Obviously this is a game-breaking experience.  Is there a solution?

  2. Boby
    Admin
    Boby avatar
    763 posts

    Posted 18 Nov 2019 Link to this post

    Hi Lisa,

    First of all thank you for trying out Fiddler Everywhere! Our plan is to work for feature parity with Fiddler in the near future, but the most used features are already intact.

    The intent of Fiddler Everywhere is similar to what Fiddler does - by default it temporarily changed the proxy settings for the main network connection, pointing all traffic to the port Fiddler Everywhere is listening. It should set the proxy settings on start and revert the original settings on (normal) exit. The problem with the proxy settings are relatively common as it happens the process to crash (or be killed) which prevents revert of the original settings. 

    We will need more information trying to diagnose the problem, for example:

    - What are the exact errors you are seeing in the browser?

    - When you do the proxy settings manual reset, is there any settings left (e.g. proxy server set to 127.0.0.1:8866 or similar)? This would be an indication that Fiddler Everywhere cannot exit normally. You also mention that this doesn't fix the network problem - did you find a way to fix it eventually and if yes, what was the culprit?

    - Are you using the latest Fiddler Everywhere 0.5.0?

    - What are the network connection types you are using (WiFi, Ethernet, Tethering, etc.)?

    - Could you send us the application logs, located in '%temp%/Progress Telerik Fiddler/Logs'?

    Regards,
    Boby
    Progress Telerik

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  3. Lisa
    Lisa avatar
    2 posts
    Member since:
    Nov 2019

    Posted 18 Nov 2019 in reply to Boby Link to this post

    Hi Boby.  First, to fix the problem, I uninstalled Fiddler and had to restart my machine after for manually resetting my system proxy settings to work.  I reinstalled today to check for specific error codes and the issue thankfully seems to be resolved!  That said, I still want to provide as much assistance for your team as possible because I'm sure others are having the same issue.

    - The errors were generic errors telling me to check my proxy status, make sure that there was nothing blocking the browser's access.

    - When I reset the proxy settings, I encountered both situations where they were completely empty, nothing to reset but still have the internet access issue, and they were populated with 127.0.0.1:8866.  I was exiting Fiddler using the 'Quit' option from the menu and still encountered the problem.

    - I was using 0.5.0 and am again today, yes.

    - My connection is WiFi.  I encountered the problems when not using my employer's VPN.  I was directly on the network. Today when I am not experiencing problems I am on home WiFi, using the VPN.

    Unfortunately I have no logs to send as I uninstalled and am error free in this fairly short time.  If I have the problem again I will immediately send you the logs.

    Thank you!

  4. Boby
    Admin
    Boby avatar
    763 posts

    Posted 20 Nov 2019 Link to this post

    Hello Lisa, 

    Thank you for the involvement and the additional information. It's good to hear that the issue is resolved for now, and we will be glad if you send us additional information and/or logs if you manage to reproduce it again. 

    And stay tuned for a new release soon!

    Regards,
    Boby
    Progress Telerik

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  5. Yuriy
    Yuriy avatar
    2 posts
    Member since:
    Mar 2020

    Posted 03 Mar Link to this post

    Hi Boby,

    I'm experiencing the same problem.

     

    I installed Fiddler -> removed it -> internet connection is broken

     

    so I went to Network -> Proxies and unselected  127.0.0.1:8866. Everything worked well until I rebooted my mac.

    After the reboot, Internet connection is back but.. my localhost web site (run by Apache web server) doesn't work.

    Please help,
    -Yuriy

  6. Yuriy
    Yuriy avatar
    2 posts
    Member since:
    Mar 2020

    Posted 03 Mar Link to this post

    well.. after doing random things (that included installing and removing Fiddler one more time and playing with Network -> Proxies settings) my Internet Connection as well as Apache web server are back working.

    Thank you guys for providing such a good tool as Fiddler. I would suggest you to try reproducing the steps on my post above and resolve the problem. Note, before you do it please make sure Apache web server is installed and works well.

    Best regards,
    Yuriy Sernivka
  7. Boby
    Admin
    Boby avatar
    763 posts

    Posted 04 Mar Link to this post

    Hello Yuriy,

    Thanks for the suggestions and the kind words!

    Fiddler basically works by setting itself as system proxy and sniffing the system traffic. On Mac, this requires administrative privileges, so a message requiring admin credentials pops up. On top of that, the same credentials are needed when the system proxy settings are reverted to the original settings on Fiddler shutdown. More often that not, on Fiddler shutdown, users just press the Cancel button on the credentials prompt, effectively leaving the proxy settings changed. 

    We are currently trying to limit the scope of the issue by not prompting for credentials when the user already have the needed permissions; we are trying some other ideas as well, so hopefully next versions will have improvements in the behavior.

    Regards,
    Boby
    Progress Telerik

    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal and vote to affect the priority of the items
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