I have Fiddler up and running on box A. I can see all traffic from my local machine and my autoresponders are working as expected.
On my Android cell phone I have set up the network to use box A as proxy. The pages are being rendered in the Android browser as expected and autoresponders are giving the correct data as expected, but none of the traffic is showing in the Fiddler UI.
Any idea?
If the AR is working, but you do not see any traffic, that would probably indicate some filters applied. Check if you are capturing traffic from all processes (see here) and any filters turned on.
Check if you have installed and trusted the FIddler root certificate as described in this article https://docs.telerik.com/fiddler/configure-fiddler/tasks/configureforandroid#decrypt-https
Check if the option "Allow remote computers to connect (unsafe)" is enabled in the Fiddler Classic application.