WatchOS app cannot start with error Domain: "IDELaunchErrorDomain Code: 15" on Xcode 11 beta

Question

Want to run app under watchOS getting error under Xcode beta: 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

My solution was to add to watch app scheme iOS target like in screenshot:

However I reported to Apple about such behavior.

Answer 2

This happened to me after modifying the bundle identifier. Following these steps works for me:

• Delete all the Schemes
• Select the WatchKit App target and under General > Embedded Content remove the WatchKit Extension
• Select the WatchKit Extension target and under Info > NSExtension > NSExtensionAttributes > WKAppBundleIdentifier make sure it is the same identifier the WatchKit App
• Clean Build (just in case)
• Select again the WatchKit App target and under General > Embedded Content add the WatchKit Extension
• Add a new Scheme for the WatchKit App
• Edit the new Scheme and in Build add a the target for: (credits to Evgeny Zrorin)
  • The iOS App target if your WatchKit App is a companion of an iOS App
  • The iOS target generated by Xcode if your WatchKit App is a standalone App

You must have 2 targets in your Scheme > Build, run your app and good luck