AppEngine Connected Android Project: sendNoRetry: Unauthorized - need token

i have created a new 'AppEngine Connected Android Project' with the Wizzard and entered my registred Mail-Adress. I changed nothing on the Registration-Code, that is created automatically, but I get the following Error erverytime I try to send a Message:

com.google.android.c2dm.server.C2DMessaging sendNoRetry: Unauthorized - need token

I tried to create a new dataMessagingToken.txt (create a new Project, with the same Name and replace it in the original one) but that does not work...

I hope you can help me. Thank You Tobi