Hi there, we have a Windows 2008 (R1, SP2) x64 server. When backing up, we were getting errors relating to VSS. Further investigation yields the following results: Running 'VSSADMIN LIST WRITERS' results in "Error: Unexpected failure: Catastrophic Failure" THe Application Log has two relevant errors. Event ID 32, Source: VSS " Volume Shadow Copy Service error: The VSS Coordinator class is not registered. This may be caused due to a setup failure or as a result of an application's installer or uninstaller. Operation: Instantiating VSS server " Immediately followed by: Event ID: 8193, Source: VSS " Volume Shadow Copy Service error: Unexpected error calling routine CoCreateInstance. hr = 0x80040154. Operation: Instantiating VSS server " Now, I've found the Windows 2003 article that advises deleting the EventSystem Subscriptions key and re-registering some DLLs - but, that produced some very odd results - none of which got VSS working, and as I understand it this method of reregistering DLLs and repairing VSS is not applicable on Windows 2008 x64. I'd like to know what steps I can take to repair VSS on this server - there must be some way of repairing the components? All help greatly appreciated! -- Mark Lomas

Hi Mark, Have you ever try this KB http://support.microsoft.com/kb/2009533? ScorprioTechNet Software Assurance Managed Newsgroup MCTS: Windows Vista | Exchange Server 2007 MCITP: Enterprise Support Technician | Server & Enterprise Admin | System Architect

Hi Mark, Have you ever try this KB http://support.microsoft.com/kb/2009533? Scorprio TechNet Software Assurance Managed Newsgroup MCTS: Windows Vista | Exchange Server 2007 MCITP: Enterprise Support Technician | Server & Enterprise Admin | System Architect Yeah - found that article earlier but after following it to the letter, the problem remains :( -- Mark Lomas

Hi Mark, Try the steps provided here: http://www.symantec.com/business/support/index?page=content&id=TECH70486 Also compare the key HKLM\System\CurrentControlSet\Services\VSS with a working system to see if there is any missing subkey or value. Shaon Shan |TechNet Subscriber Support in forum |If you have any feedback on our support, please contact tngfb@microsoft.com