Closing app doesn't remove proxy added

When closing the app, the proxy which was created for the live capture, is not removed.  Fiddler Classic would remove the proxy on close.

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Hey There,

We have seen issues with clearing proxy when Fiddler application closes because of process crash, and we are currently working on improving these scenarios.

But, can you please give us more details if this is consistently reproducible or happens infrequently? 

This happens when i just open the app and then close it.  When opening, since it goes right into live capture, it creates the proxy.  Then when i close it, i notice that the proxy is not removed and therefore other apps begin breaking.  So i start FidEv and stop capture and then close again and it fixes it.


Thanks for the details.

I can confirm that we are observing this issue sometimes, we are working on improving the cleanup process post app shutdown to make sure the proxy settings are cleared.

It will be great if you can share your application logs for us to analyze, you can find them in this location:

Mac: ~/Library/Application Support/Fiddler Everywhere/Logs

Win: %AppData%\Fiddler Everywhere\Logs\

Also can you please tell us if you are on Mac or Windows.

this seems to be cleared up for now.  I think there was one time it crashed and that may have caused it.

Another time i was using Classic and FE at the same time to compare them.  So i will keep an eye out for what might cause the situation.

FWIW, i like the font in Classic much better.  I like lots of data on the screen and it just seems that FE doesn't make good use of screen real-estate.  If you could allow us to change the font that would help

Thanks for confirming that you are not observing this issue for now, but feel free to drop in  a comment or share your logs if you see this issue again.

"If you could allow us to change the font that would help"

Do you mean to provide a setting to change the font size, or both font type and size? It will also be great if you can tell us your screen resolution and better yet post a screenshot on how Fiddler Everywhere looks on your computer.

i sent an email but it looks like it may not have gone through.  let me know and i can upload the files if i need to.

We got your email, thanks for the feedback Troy.

My experience with proxy: When my PC crashes with fiddler running, the proxy is not removed (obviously) But when re-powering my PC, fiddler does not start - showing white GUI. When the proxy is set off through "Settings/Proxy" the fiddler again starts fine.

Hello HCA,

What happens is that when the OS proxy settings are not reset, Fiddler can't use the active internet connection and can't access its login endpoints. So removing the leaked proxy is a must so that you could run Fiddler Everywhere successfully.

This just happened to me today,but I didn't realize it.  Got locked out of an important teams meeting because when it occurs it kills all internet http access.  

Looks like this has been a known issue for a long time with no fix.  Quick suggestion:
If you can't fix the crash, then at least have Fiddler try removing the leaked proxy (preview message from Nick Iliev) on startup, so it would go like this

  • Fiddler closes and fails to remove the proxy, so internet access is horked.
  • Start Fiddler.  It's going to fail to connect to its login endpoints because the connection was refused (no proxy)
  • Since it was connection refused, check to see if the windows proxy is set to use Fiddler
  • Fix that
  • Continue the startup process.

Wasted 2 hours trying to fix this

1) Installed Fiddler anywhere (latest) 

2) Ran it, closed it, uninstalled it

3) Nothing can connect to internet on windows (google, teams etc)

Fiddler setup will mess with your Windows proxy settings.

To fix it search for proxy in Windows menu


open proxy settings and turn off proxy


Hey everyone,

There are many reasons why the Fiddler Everywhere app could close unexpectedly: OS crash, software crash, hardware crash, security tools, network policies, administrative restrictions, etc. Any of those could result in leaked proxy settings which, as a side effect, will result in a lack of Internet connectivity.

We've created this documentation KB which explains how to revert the OS proxy settings to their default in each support OS (Windows, macOS, Linux).