Fiddler not capturing UWP traffic on Windows 10.10586.122

[Brandon H]

Before anybody tells me to use WinConfig or the Enable Loopback Utility, know that I've already done this.

I'm not trying to decrypt HTTPS traffic, either.

I'm simply trying to see *any* traffic from the UWP app I'm writing.

I've hit 'Exempt All' in the Loopback util, I've hit 'Exempt None'.

I've tried restarting the machine.

I've tried 'allow remote computers' & restarted Fiddler.

No matter what I do, MS Edge and all UWP apps are cut off from the internet while Fiddler is capturing. Normal browsers (chrome, IE proper) and other internet apps (tweetdeck, slack) all work fine as well and I see their traffic in Fiddler.

I'm coming up empty on all the searches I've done as well.

Can anybody think of something that might help? I've even gone so far as to disable the Hyper-V virtual switches that are installed as part of the Windows 10 Mobile emulator suite and that didn't help either.

Thanks for any help!

[Brandon H]

Fiddler Version: 2.6.2.2

[Eric Lawrence]

First, don't use Fiddler 2.x; use Fiddler 4.x.

What exactly happens: What do you see in the client, and what do you see in Fiddler after turning on Help > Troubleshoot? 

"Exempt none" will definitely cause any AppContainer-based applications to fail. 

It's been a long time since I've used 10.10586, but Fiddler worked fine when I used it. It also works fine with all other builds up to the latest public 10.14279.

[Brandon H]

Changed to Fiddler 4.6.2.2

I see nothing additional in Fiddler when I do Help | Troubleshoot. The site it kicks me out to (127.0.0.1:8888) also doesn't load.

B

[Eric Lawrence]

What exactly happens: What do you see in the client and/or Edge, and what do you see in Fiddler after turning on Help > Troubleshoot? 

Failure to load 127.0.0.1 strongly suggests that the client is forbidden to talk to the localhost, a condition typically resolved using the EnableLoopback tool.