“IDELaunchErrorDomain” error while running watchOS app of device

Question

Running watchOS app on real watch device getting below error.

Details:

Error Launching 'Appname Extension'
Domain: IDELaunchErrorDomain
Code: 15
Failure Reason: Build and Run launch failed as the app to run does not appear to be known by the system.

Answer 1

I had the same problem, try running on the simulator before running on device , worked for me.

Answer 2

Select your WatchKit app under your targets. Under Build Phases, expand the Dependencies section and make sure that the correct WatchKit App Extension is present there. If you duplicated your target, it is possible that an old unrelated WatchKit extension sitting over there that is creating the problem.