From some time I use a Fiddler everywhere and i have some problems with debugging a mobile app requests, beacuse some of requests are not visible in Fiddler and are blocked(mobile app displays a error).
All requestes are HTTPS and problem occuring also on Android and iOS app.
It's not a mobile app problem, beacuse my mate use it without any problems on the same app.
Ofc, certificates are installed on mobile app, fiddler setup-
Maybe someone know where is the problem and what i can do to solve this issue?
By default, most Android applications will reject any user-installed CA meaning that simply installing the certificate is not suficient. You need to modify the application codebase and change its security configuration so that explicitly allows user CAs as demonstrated here:
However, many applications also use additional security configurations like certificate pinning, which means that they expect a specific certificate and will trust only that certificate. In short, you need to have access to the application codebase (app in development) to rebuild the app will modified security configuration, and removed certificate pinning.
As i said, only some requestes are not visible and blocked, also it's configured as in documentation.
90% of requests from mobile app are visible and work fine.
"It's not a mobile app problem, beacuse my mate use it without any problems on the same app." so it's not a mobile app problem.
You can test the request that the app is making through another client (e.g., browser or cURL) and observe if it is being captured. If yes, that probably indicates that the app's request is not going through the system proxy or is not using HTTP/HTTPS as protocol.
Are you the owner of the application? If so, you could share how the request is made and which requests are not going through. Also, what exactly do you mean by "my mate use ut without any problem" - does that mean your mate uses Fiddler Everywhere with the very same application and captures all the traffic, but you are not?
" does that mean your mate uses Fiddler Everywhere with the very same application and captures all the traffic, but you are not?"
Exactly and this is why i said "it's not a problem with mobile app".
Some of networking of this specific mobile app are visible in Fiddler, also all of requests using HTTP/HTTPS protocol.
Additionaly information - it's happening often but on different requests.
Problem occurring on both platform - Android and iOS.
Thank you for the additional information!
Still, without an actual example that we can use for reproduction, it is hard to say what might be happening. If possible, provide a codebase that sends a problematic request or the link to the application that we are talking about,