tnx that was the trick.
The "keybackup"doesn’t do anything.
But with “C:\Users\USERNAME\AppData\Roaming\Musicoin\keystore” it works.
The first wallet I made on another pc but didn’t sync there.
So I made a new one on another pc.
Now that I copied the the walletfile from the old pc keystore to the keystore on the wallet I use now it’s is ok.