I’m getting the error “developer does not own the app id being forked” when trying to duplicate an App Engine app. I’m following the instructions here, to migrate an app from the Master/Slave Datastore to the HRD.
I definitely own the app; I’m the only person listed as an owner, and I’ve managed to duplicate other apps I own. This happens whether I’m signed in to multiple accounts or just the one.
What could be going wrong here?
Edit: I’ve opened an issue about this here: http://code.google.com/p/googleappengine/issues/detail?id=8106
The App Engine team have now given a workaround, which is to give owner permissions to another @gmail.com account and do the duplication from there. It worked for me!