Can't start debugserver on iPhone device Xcode 7.1 error

Question

When I run the iOS device, Xcode is giving me a error...

Could not start debug server on "iPhone" when trying to launch "Monster"

This never happened before, why is this happening now? What is this? What do I do?

Answer 1

I have been seeing this issue now with Xcode 9.

What fixes it for me is restarting the device.

Hope that helps.