How to fix the error "Unable to open debugger port " in Android Studio?
In my case, there was another service running on my laptop(Windows) that was using the port 8600. I opened Task Manager and stopped the service. Now, I could debug my application normally without the above error.
Try Restarting ANDROID STUDIO (Worked for me)
I was able to fix this with these commands:
adb kill-server
adb start-server