Hast Du auf Deinem WSUS das Patch KB2720211 schon eingespielt? Wenn nicht könnte Dien Problem daher kommen. Dein Client hat sich offensichtlich schon die neue Windows Update Version 7.6.7600.256 geholt.
Siehe auch hier:
(Du musst Dich Einloggen oder Registrieren um Multimediadateien oder Links zu sehen).

Darauf deutet auch dieser Fehler hin:
WARNING: Digital Signatures on file C:\Windows\SoftwareDistribution\SelfUpdate\wuident.cab are not trusted

UMeadow schrieb on 25.06.12 um 16:08:03:



Genau dort lag das Problem. Bevor ich diesen Fehler hatte, haben die Clients tw. keinen Status geschickt,auch dies ist nach Durchführung dieses Lösungsweges erledigt und der WSUS läuft wie er soll. 

Folgend der Lösungsweg von (Du musst Dich Einloggen oder Registrieren um Multimediadateien oder Links zu sehen).


This page helped alot. Let me recap for others on the interwebs.

Cause:

- Applied KB2720211 to a WSUS 3.0 SP2 server thats running on Windows 2008 64 bit server with local SQL db.

What happened:

- I could no longer sync my WSUS server with the interwebs.
- clients could still connect to WSUS and I could still open the WSUS console.
- Uninstalled WSUS, left DB and downloads and reinstalled WSUS in attempt to fix broken syncing.
- Clients could now no longer sync with WSUS server. (They got Windows Update error code 800B0001).

Solution:

- Googled, found this page.
- Followed just these last few steps that Chucker2 posted.

    Extract necessary files from 2720211 installer

    -Download the KB2720211 installer for your architecture from Microsoft ( (Du musst Dich Einloggen oder Registrieren um Multimediadateien oder Links zu sehen).)
    -Extract WUSSetup.msp from the installer by running the installer with the /extract parameter (example: "WSUS-KB2720211-x64.exe /extract")
    -With 7-zip, open WUSSetup.msp and extract "PCW_CAB_SUS".
    -With 7-zip, open "PCW_CAB_SUS" and extract "DbCert", "DbCertDll", and "DbCertSql".
    -Rename those files to "WSUSSignDb.cer", "WSUSSignDb.dll", and "WSUSSignDb.sql", respectively.
    -On your WSUS server, navigate to "C:\Windows\SYSMSI\SSEE\MSSQL.2005\MSSQL\SchemaSig" and copy the extracted "WSUSSignDb.cer" and "WSUSSignDb.dll" to it. Make a backup copy of the two existing versions, just in case.
    -On your WSUS server, navigate to "C:\Program Files\Update Services\Database" and copy the extracted "WSUSSignDb.sql" to it. Make a backup copy of any existing versions of the file.
    -Reinstalled 2720211

PROBLEM FIXED AND CLIENTS COULD ALL SYNCH AGAIN.

Thanks Chucker 2.

ps. Susan Bradley stop polluting every WSUS post on the interwebs with your constant links to WSUS KB2720211 : Common issues encountered and how to fix them