Android – Google Maps API V2 – authentication errors always occur

I've found a lot of questions about this - I'm ashamed myself

But no matter how hard I try, I'm simple and can't run the Maps API at all!

Instead of using the demo project com. Example. Mapdemo, instead of my own project

I must have registered my debug.keystore SHA1 fingerprint. Now my application and com.example - I also tried the browser API key. Everyone said it was OK

But not

I always get:

06-16 11:21:29.860: E/Google Maps Android API(2382): Authorization failure.  Please see https://developers.google.com/maps/documentation/android/start for how to correctly set up the map.

I'm really happy and really angry. How can I not completely describe this problem so that people who can program Android applications can follow and succeed?

What about?

Can someone tell me what else could be wrong?

Add ons: I set all the contents according to the specifications, obtained my key from my debug.keystore, tried map demonstration with com.example, and used my own application package. No. plus: that stupid empty window. What's going on