How to solve: Embedded binary is not signed with the same certificate

Question

My Parent app IS signed correctly. I have verified in every screen. Has anyone seen this?

It's complaining about my watchKit app.

Thanks!

XCode 10.0 beta 6

error: Embedded binary is not signed with the same certificate as the parent app. Verify the embedded binary target's code sign settings match the parent app's.

  Embedded Binary Signing Certificate: Software Signing
  Parent App Signing Certificate: - (Ad Hoc Code Signed)

Answer 1

The problem had nothing to do with the signing. The answer for me was to paste $(ARCHS_STANDARD) into the project valid architecture field. Incredible!