I have the following situation:
1. A Universal App running in Windows 10 that contains a WebView and SocketListener that listens on port 9000.
2. An HTML5 game that is launched inside the WebView which then does a loopback connection to port 9000 on the same PC to the SocketListener that is listening for the traffic.
3. The SocketListener forwards requests to a server on the back-end and does some man-in-the-middle caching of things, and then responds to the requesting WebView.
In other words, the requesting WebView and the responding SocketListener / Proxy are both inside the SAME application.
Fiddler DOES see the comms leaving the Webview (the initial request anyway), but for some unknown reason it never receives a response from my custom proxy listening and responding on port 9000. It just times out.
I have done the following:
1. Set an exemption for the relevant universal app and confirmed the exemption with the relevant command line tools in Win10.
2. Flushed the Fiddler certificates and re-installed them as per your instructions here:
3. Tried every variant of "localhost" I can come up with including: "localhost.", "fiddler.ipv4", "fiddler.localhost", "machinename" etc. etc.
But to be honest I don't even think this is the issue anyway because Fiddler DOES see the requests from the WebView and log them, it just won't forward them.
4. Checked firewall settings.
I've been trying to sort this out for hours now but I just don't know what else to try here.
I actually had this working a few weeks ago, but now it's stopped working again, and for the life of me I cannot understand why.
I've been through all the online help and suggestions, tried multiple things I've read in various forum posts and articles, and still cannot get it to work.
The thing is, my problem is not the usual "Fiddler doesn't see Localhost traffic". It DOES see localhost traffic, it just seems to be refusing to forward that traffic to port 9000, also on localhost and refuses to talk to that custom proxy of mine listening on port 9000.
Any suggestions ? I'm at a complete loss to understand why this refuses to work.