error: WatchKit Extension doesn\'t contain any WatchKit apps.
Verify that the value of WKWatchKitApp in your WatchKit App\'s Info.plist is set to YES.
I had changed the autogenerated Bundle ID and then hit the same error.
I found that the value in the WatchKit Extension plist needed to get updated. Do a global search on this "WKAppBundleIdentifier" and then make it match the bundle id of your WatchKit app. This fixed the error for me.
I found that in extension sources it was pointing to Debug-iphoneos location of WatchKitApp so readding it fixed the problem
this solved the problem for me:
afterwards clean and rebuild