Cant autorise my pc for Adobe Digital Edition.

[Guest]

Cant autorise my second pc with my Adobe ID for Adobe Digital Edition. I just have Adobe Digital Edition an my Netbook (which i dont use anymore) and Smartphone. Now i wanted to read my eBooks on my main Computer and i got an error when i try to autorise my eBookReader. Can anyone activate this Pc for my Adobe Digital Edition?

[Guest]

Because noone is answering me, i try again.
Im sorry that im german and hope someone can understand this:

Wie viele Geräte lassen sich aktivieren?

Sie können bis zu sechs Computer oder mobile Geräte aktivieren und geschützte PDF-Dateien gemeinsam auf ihnen verwenden.

It means that i can have 6 gadgetry autorisied and i just have 1 and should be able to autorise this pc.

Thats the Error massage i got: