O.K.This is getting frustrating.SBS Server 2003 SP2Attempting to eliminate a VSS Error 11 I uninstalled/reinstalled the COM+ service as was suggested.I have re-registered theVSS dll'sseveral times and rebooted, most recently this morning.regsvr32 ole32.dllregsvr32 vss_ps.dllVssvc /Registerregsvr32 /i swprv.dllregsvr32 /i eventcls.dllregsvr32 es.dllregsvr32 stdprov.dllregsvr32 vssui.dllregsvr32 msxml.dllregsvr32 msxml3.dllregsvr32 msxml4.dllIt looks to me like I'm close. Perhaps I'm missing a dll I need to register. Full text of error messages below. **************************************Event Type:ErrorEvent Source:VSSEvent Category:NoneEvent ID:20Date:10/24/2008Time:6:36:07 AMUser:N/AComputer:TPC-SBSDescription:Volume Shadow Copy Service error: A critical component required by the Volume Shadow Copy service is not registered. This might happened if an error occurred during Windows setup or during installation of a Shadow Copy provider. The error returned from CoCreateInstance on class with CLSID {790f2886-9889-4c99-8ef5-531add05d044} and Name SW_PROV is [0x80040154]. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.Data:0000: 2d 20 43 6f 64 65 3a 20 - Code: 0008: 43 4f 52 53 4f 46 54 43 CORSOFTC0010: 30 30 30 30 30 30 38 30 000000800018: 2d 20 43 61 6c 6c 3a 20 - Call: 0020: 43 4f 52 53 4f 46 54 43 CORSOFTC0028: 30 30 30 30 30 30 36 35 000000650030: 2d 20 50 49 44 3a 20 20 - PID: 0038: 30 30 30 30 37 31 35 36 000071560040: 2d 20 54 49 44 3a 20 20 - TID: 0048: 30 30 30 30 39 33 36 38 000093680050: 2d 20 43 4d 44 3a 20 20 - CMD: 0058: 43 3a 5c 57 49 4e 44 4f C:\WINDO0060: 57 53 5c 53 79 73 74 65 WS\Syste0068: 6d 33 32 5c 76 73 73 76 m32\vssv0070: 63 2e 65 78 65 20 20 20 c.exe 0078: 2d 20 55 73 65 72 3a 20 - User: 0080: 4e 54 20 41 55 54 48 4f NT AUTHO0088: 52 49 54 59 5c 53 59 53 RITY\SYS0090: 54 45 4d 20 20 20 20 20 TEM 0098: 2d 20 53 69 64 3a 20 20 - Sid: 00a0: 53 2d 31 2d 35 2d 31 38 S-1-5-18 Event Type:ErrorEvent Source:VSSEvent Category:NoneEvent ID:12292Date:10/24/2008Time:6:36:07 AMUser:N/AComputer:TPC-SBSDescription:Volume Shadow Copy Service error: Error creating the Shadow Copy Provider COM class with CLSID {790f2886-9889-4c99-8ef5-531add05d044} [0x80040154]. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.Data:0000: 2d 20 43 6f 64 65 3a 20 - Code: 0008: 43 4f 52 53 4f 46 54 43 CORSOFTC0010: 30 30 30 30 30 30 38 37 000000870018: 2d 20 43 61 6c 6c 3a 20 - Call: 0020: 43 4f 52 53 4f 46 54 43 CORSOFTC0028: 30 30 30 30 30 30 36 35 000000650030: 2d 20 50 49 44 3a 20 20 - PID: 0038: 30 30 30 30 37 31 35 36 000071560040: 2d 20 54 49 44 3a 20 20 - TID: 0048: 30 30 30 30 39 33 36 38 000093680050: 2d 20 43 4d 44 3a 20 20 - CMD: 0058: 43 3a 5c 57 49 4e 44 4f C:\WINDO0060: 57 53 5c 53 79 73 74 65 WS\Syste0068: 6d 33 32 5c 76 73 73 76 m32\vssv0070: 63 2e 65 78 65 20 20 20 c.exe 0078: 2d 20 55 73 65 72 3a 20 - User: 0080: 4e 54 20 41 55 54 48 4f NT AUTHO0088: 52 49 54 59 5c 53 59 53 RITY\SYS0090: 54 45 4d 20 20 20 20 20 TEM 0098: 2d 20 53 69 64 3a 20 20 - Sid: 00a0: 53 2d 31 2d 35 2d 31 38 S-1-5-18 Event Type:ErrorEvent Source:VSSEvent Category:NoneEvent ID:20Date:10/24/2008Time:6:36:07 AMUser:N/AComputer:TPC-SBSDescription:Volume Shadow Copy Service error: A critical component required by the Volume Shadow Copy service is not registered. This might happened if an error occurred during Windows setup or during installation of a Shadow Copy provider. The error returned from CoCreateInstance on class with CLSID {790f2886-9889-4c99-8ef5-531add05d044} and Name SW_PROV is [0x80040154]. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.Data:0000: 2d 20 43 6f 64 65 3a 20 - Code: 0008: 43 4f 52 53 4f 46 54 43 CORSOFTC0010: 30 30 30 30 30 30 38 30 000000800018: 2d 20 43 61 6c 6c 3a 20 - Call: 0020: 43 4f 52 53 4f 46 54 43 CORSOFTC0028: 30 30 30 30 30 30 36 35 000000650030: 2d 20 50 49 44 3a 20 20 - PID: 0038: 30 30 30 30 37 31 35 36 000071560040: 2d 20 54 49 44 3a 20 20 - TID: 0048: 30 30 30 30 39 33 36 38 000093680050: 2d 20 43 4d 44 3a 20 20 - CMD: 0058: 43 3a 5c 57 49 4e 44 4f C:\WINDO0060: 57 53 5c 53 79 73 74 65 WS\Syste0068: 6d 33 32 5c 76 73 73 76 m32\vssv0070: 63 2e 65 78 65 20 20 20 c.exe 0078: 2d 20 55 73 65 72 3a 20 - User: 0080: 4e 54 20 41 55 54 48 4f NT AUTHO0088: 52 49 54 59 5c 53 59 53 RITY\SYS0090: 54 45 4d 20 20 20 20 20 TEM 0098: 2d 20 53 69 64 3a 20 20 - Sid: 00a0: 53 2d 31 2d 35 2d 31 38 S-1-5-18 Event Type:ErrorEvent Source:VSSEvent Category:NoneEvent ID:12292Date:10/24/2008Time:6:36:07 AMUser:N/AComputer:TPC-SBSDescription:Volume Shadow Copy Service error: Error creating the Shadow Copy Provider COM class with CLSID {790f2886-9889-4c99-8ef5-531add05d044} [0x80040154]. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.Data:0000: 2d 20 43 6f 64 65 3a 20 - Code: 0008: 43 4f 52 53 4f 46 54 43 CORSOFTC0010: 30 30 30 30 30 30 38 37 000000870018: 2d 20 43 61 6c 6c 3a 20 - Call: 0020: 43 4f 52 53 4f 46 54 43 CORSOFTC0028: 30 30 30 30 30 30 36 35 000000650030: 2d 20 50 49 44 3a 20 20 - PID: 0038: 30 30 30 30 37 31 35 36 000071560040: 2d 20 54 49 44 3a 20 20 - TID: 0048: 30 30 30 30 39 33 36 38 000093680050: 2d 20 43 4d 44 3a 20 20 - CMD: 0058: 43 3a 5c 57 49 4e 44 4f C:\WINDO0060: 57 53 5c 53 79 73 74 65 WS\Syste0068: 6d 33 32 5c 76 73 73 76 m32\vssv0070: 63 2e 65 78 65 20 20 20 c.exe 0078: 2d 20 55 73 65 72 3a 20 - User: 0080: 4e 54 20 41 55 54 48 4f NT AUTHO0088: 52 49 54 59 5c 53 59 53 RITY\SYS0090: 54 45 4d 20 20 20 20 20 TEM 0098: 2d 20 53 69 64 3a 20 20 - Sid: 00a0: 53 2d 31 2d 35 2d 31 38 S-1-5-18

Hi Brett, Based on the research, this issue may be occurred due to some DLL files were not successfully registered on the system. Therefore, I would like to suggest that we re-register the related DLL files again by using the steps below. Open a command-prompt on the problematic server, and type the following commands to manually register the following VSS DLL's. cd %windir%\system32 regsvr32.exe /i eventcls.dll regsvr32.exe /i swprv.dll regsvr32.exe vssui.dll regsvr32.exe vss_ps.dll regsvr32.exe msxml.dll regsvr32.exe msxml2.dll regsvr32.exe msxml3.dll regsvr32.exe ole32.dll regsvr32.exe oleaut32.dll regsvr32.exe es.dll vssvc /register If the above steps don't resolve the issue, please check and verify the "Task Scheduler" service is Started. After a reboot, please check if the issue can be resolved. Hope it helps. David Shen - MSFT