Unable to capture Android traffic in Fiddler Classic

[Dave]

I am following the below documentation in order to view the traffic from an Android device. However, my traffic is not being captured in Fiddler and when I have the manual proxy settings enabled then my device appears to block any traffic. Could you help please? Are there any other instructions that I can follow?

https://docs.telerik.com/fiddler/configure-fiddler/tasks/configureforandroid#configure-android-device

Thanks. 

[Nick Iliev]

Hello Dave,

 

Apart from the Fiddler Classic documentation article you've followed, you can also check the section for configuring an Android device alongside Fiddler Everywhere documentation (the only difference compared to the FIddler Classic setup is the used Fiddler port which for Fiddler Classic is port 8888). That said, if the device configuration is as described, there might be a different reason for your issue appearing.

- Check and verify that both the Fiddler host machine and the target Android device are using the same network and are discoverable. If the Fiddler host machine has multiple active network adapters, try disconnecting all of them except the one used on the Android device. Then test if the Android device can be pinged from the Fiddler host machine. 

- Ensure that the Fiddler Classic proxy port is opened on both the host and the target device. By default, the Fiddler Classic uses port 8888 (whereas FIddler Everywhere uses 8866).

- Close any active VPN connections.

- Try to disable any third-party security tools or to allowlist Fiddler Everywhere within their security policies (might require your network administrator permission).

- Once the Fiddler Classic proxy is set as a manual proxy on your Android device, try to load the echo service address at http://ipv4.fiddler:8866. In case the address is successfully loading, that indicates that you can use the proxy (and you can proceed with installing the Fiddler Root CA so that you will be able to decrypt HTTPS) traffic. If at that point, you cannot load the above address, that indicates that the Android device is not "seeing" the proxy, and you probably need to consult your network administrator.

Note that upon successful configuration, you should be able to capture any mobile browser HTTP/HTTPS traffic, but you won't be able to capture traffic from most Android applications. If you want to capture traffic from a specific Android application, refer to the configuration described in this documentation article.

 

Regards,
Nick Iliev
Progress Telerik