Unable to attach debugger in Android Studio - localhost:8600 java.net.ConnectException

Question

I cannot attach the debugger in Android Studio while running debug on a phone.

I’m currently using a Samsung S4, running Android 4.4.4 (but have tried an S5, S6, S7, and

Answer 1

I just experienced the same issue. It seems, as if Android Studio Version 2.2 has some issues with a non-attaching debugger as you can see for example here and here.

In my case the following helped:

• Remove the launch profile for your app by going to Run -> Edit Configurations... and removing the profile there. Don't forget to hit the OK button after you have removed the profile. :)
• Create a new launch profile from scratch by again going to Run -> Edit Configurations..., hitting the + button, selecting an Android App launch profile and selecting your start module. The other default values of the profile were just fine.

Hope this helps you as well.