Adb Devices can't find my phone

Try doing this:

• Unplug the device
• Execute adb kill-server && adb start-server(that restarts adb)
• Re-plug the device

Also you can try to edit an adb config file .android/adb_usb.ini and add a line 04e8 after the header. Restart adb required for changes to take effect.

I have a Samsung Galaxy and I had the same issue as you. Here's how to fix it:

In device manager on your Windows PC, even though it might say the USB drivers are installed correctly, there may exist corruption.

I went into device manager and uninstalled SAMSUNG Android USB Composite Device and made sure to check the box 'delete driver software'. Now the device will have an exclamation mark etc. I right clicked and installed the driver again (refresh copy). This finally made adb acknowledge my phone as an emulator.

As others noted, for Nexus 4, you can also try this fix.

I did the following to get my Mac to see the devices again:

• Run android update adb
• Run adb kill-server
• Run adb start-server

At this point, calling adb devices started returning devices again. Now run or debug your project to test it on your device.