A Firewall may be blocking Fiddler's traffic

I am using glasswire for several month. But recently I faced a problem that glasswire block all connection for firefox

Here is the message I got to open any website -

" The connection to ‘www.aol.com’ failed. A Firewall may be blocking Fiddler’s traffic.
Error: AccessDenied (0x271d).System.Net.Sockets.SocketException An attempt was made to access a socket in a way forbidden by its access permissions "

If I off galsswire then firefox work as normal.

How do I fix this issue its only happen in firefox. I use Firefox version 46. & I dont want to upgrade cause one add in I use not works in lattest version

Plz help thanks


I have never heard of this issue before. Can you uninstall GlassWire, then go to your firewall settings and choose “restore defaults” then try to use Fiddler/Firefox again and see if you still have the problem?

If the problem is solved install GlassWire again with its “clean” installer option, then check again.

If you search on this error message then you will find that Fiddler has issues when running alongside anti-virus/security programs and even has problems with some security features built into web browsers. The main concern for security and network monitor programs is that Fiddler does the same sort of stuff that malware sometimes does: changing Internet connection settings, forcing web-browsing traffic through a proxy, and inspecting and modifying packet contents.

The actual error varies but the main symptom is no connection through the Fiddler proxy, e.g. http://www.tomshardware.com/answers/id-2711677/internet-shows-connected.html. It is not a reason to do anything with your web browser, whether Firefox or Chrome or whatever.

You’ve seen that stopping GlassWire “fixes” the problem. But I’m confident that the problem also goes away if you uninstall Fiddler or stop Fiddler capturing data: That is what this Fiddler user found:

If I close Fiddler or disable the capture mode my internet come back to normal.
Uninstall and reinstall Fiddler does not solve the problem, neither restart Windows.​

For most users I’d recommend that you uninstall Fiddler before GlassWire. What troubles me about your situation is that you are using a sophisticated tool like Fiddler in conjunction with a consumer-ready tool like GlassWire. If you’re not an application developer or network technician then Fiddler is overkill. If you are expert enough to use Fiddler properly then you don’t really need GlassWire.

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