For climate-prediction the detailed BOINC-stats gives my correct stats: 17,249.44.
The Boinc-Manager on my both systems gives 594.59 stats.
How can I correct this? (Update does'nt work).

The BoincStats gives much more credits for Climate prediction and Einstein@Home then the BoincManager on my systems.
An update should fix this, but it doesn't.

I would guess that you have two CPDN accounts. Have you attached/reattached/started using BAM! recently? You may have made a new account instead of finding the old account. If that is the case I advise changing to the account with more credit then abandoning the other account.

Keck_computers is right, if you search for your name, you'll find two different identities, both with a CPDN account. The same is true for your einstein@home account. Email addresses are unique, so you have signed up with 2 different email adresses.