Several problems with Digital Editions

I have several problems with Digital Editions.

First: I bought and downloaded a new ebook today.
When I wanted to open it and finish the download/licensing I had a problem report: E_AUTH_BAD_DEVICE_KEY_OR_PKCS12

Second: Because of I fault I removed the Adobe-ID from my E-Reader. When I wanted to ad it again ther was also a problem report.
It means something like: Digital Editions has found a fault at the activations server. (Digital Editions hat einen Fehler auf dem Aktivierungsserver festgestellt.)

Third: When I try to open a eBook I already have at Digital Editions there comes this message: Licenskey is broken.

Please help me to solve this three problems so I can use Digital Editions, my eReader and eBooks again!
Thank you!