Acronis Backup&Recovery 10 Advanced Server SBS Edition: no backup possible anymore

Hi.
Since Sunday, our SBS 2008 doesn´t make any backups anymore on our NAS system.
I checked the log file and found the following info:

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Details
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Typ: Fehler
Datum und Zeit: 25.09.2011 23:58:23
Backup-Plan: [Keine]
Task: [Keine]
Code: 11.468.816(0xAF0010)
Modul: 175
Besitzer: admin
Nachricht:
Herstellen der Remote-Verbindung fehlgeschlagen: Remote-Verbindungen sind unwirksam gemacht.
Zusätzliche Info:
--------------------
Fehlercode: 16
Module: 175
LineInfo: 1b28a72e6916e8c0
Felder: $module : C:\Program Files (x86)\Acronis\BackupAndRecovery\mms.exe
Nachricht: Herstellen der Remote-Verbindung fehlgeschlagen: Remote-Verbindungen sind unwirksam gemacht.
--------------------
Acronis Knowledge Base: http://kb.acronis.com/errorcode

Ereignis-Code: 0x00AF0010

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After that, i tried to manually start the task with the same error in the end.
After that, i tried to upgrade to the newest version, but during upgrage i get the following error:
"No License for the required product available on the license server".
So i downloaded my serial again for the product and wanted to read the serial file, but i got the info, that the serial is not correct for this product.
After that, i tried to go on with updating.
The update started just fine, but during updating the license server i get the following error:

Code: 06442537
Zeilenkennung: 0x394351065f8e4bad
Nachricht: Installationsfehler.

Suberror
Code: 01603
Zeilenkennung: 0xbd28fdbd64edb8bc
Nachricht: Schwerwiegender Fehler bei der Installation

So now i don´t know how to go on.
I also restarted our SBS without any luck.
How can i go on making backups?
Thanks for your help.