Works on Simulator, fails on device: error: WatchKit App doesn't contain any WatchKit Extensions

Question

I am seeing the following error when trying to run a project on a real device, in the simulator it runs fine.

error: WatchKit App doesn't contain any WatchKit Extensions. Verify that the value of NSExtensionPointIdentifier in your WatchKit Extension's Info.plist is set to com.apple.watchkit

Things which may or may not be relevant

• I am using cocoa pods in both the watch and main app target
• The project is mostly objective-c but has a few swift files
• Xcode 8.1 (8B62)
• Device Software Versions: iOS 10.1.1 & WatchOS 3.1
• Deployment Info > Deployment Target: iOS 10.0 watchOS 3.0

Things I’ve tried

• I have checked several times that all the correct files belong to the watch target. I may have missed something here, but I assume it wouldn’t run on the simulator if this was the case
• Bundle identifiers
  • main app’s identifier: < app id >
  • watch app’s bundle identifier: < app id >.watchkit
  • watch app’s WKCompanionAppBundleIdentifier: < app id >
  • watch extension’s bundle identifier: < app id >.watchkit.extension
  • watch extension’s NSExtension>NSExtensionAttributes>WKAppBundleIdentifier: < app id >.watchkit
• NSExtension>NSExtensionPointIdentifier: com.apple.watchkit
• WKWatchKitApp is set to YES in both the Watch Extension and the Watch App
• I have removed and re-added the .appex from Build Phases>Embed App Extensions
• Ensuring Mach-O Type is set to executable in all targets
• Re-installing pods as described in this answer
• Clearing derived data
• Clearing build folder
• Restarting Xcode
• I tried an archive and this failed with the same error

In lieu of an answer, advice on debugging / troubleshooting this would be appreciated too.

Answer 1

I've seen this intermittently, but usually rebuilding a second time fixed it. I've never got to the bottom of why.

I've always assumed it's a bug in Xcode.

Sorry can't be more help, but you're not alone in seeing this.