Symptoms 

System state backups start to fail on SBS2011 or servers with SharePoint 2010 installed on them. Additionally, when backups attempt to take a VSS snapshot, the backup job may stall for 30 minutes (and eventually the watchdog timer will force the backup process to end) or the backup log may fail the VSS snapshot and have messages like:

INFO: Initializing open file backup [E:\] {VSS-WS03.dll}
INFO: VSS: ERROR: Win32 call "GetVolumePathNameW((LPCWSTR)pathTemp.c_str(), WString2Buffer(volumeRootPath), (DWORD)volumeRootPath.length())" failed.
INFO: VSS: ERROR: - GetLastError() == 123
INFO: VSS: ERROR: - Error text: The filename, directory name, or volume label syntax is incorrect.

Backups might only start to fail after windows updates have been applied, or SharePoint-specific updates. 

Possible Causes 

In versions of SharePoint prior to SharePoint 2010, after a patch was applied, SharePoint would automatically upgrade the databases (if necessary) to the latest format. Apparently this was causing pain for administrators with large SharePoint databases, because these processes could take a long time, which wasn't expected during the windows update procedure. So instead, in SharePoint 2010 (and later presumably), patches are applied, but the databases are not upgraded automatically. Instead, after SharePoint patches are applied, the administrator must manually run commands to upgrade the SharePoint databases.

While the SharePoint databases are in this 'not fully upgraded' state, SharePoint will continue to work; however, this is an 'unsupported' configuration and things like the SharePoint VSS writer will fail, causing VSS snapshots or system state backups to fail. 

For more information, please refer to the following links: 

• http://blogs.technet.com/b/sbs/archive/2011/05/24/you-must-manually-run-psconfig-after-installing-sharepoint-2010-patches.aspx 
• http://technet.microsoft.com/en-us/library/ff806326.aspx 

Resolution 

You can upgrade the SharePoint databases by running the PSConfigUI.exe command, or by using the PSConfig.exe command line utility. To use the command line utility, do the following:

1. Open an Administrative command prompt (task manager, show all processes, file -> run). 
2. Change directory to C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN 
3. Run PSConfig.exe -cmd upgrade -inplace b2b -force -cmd applicationcontent -install -cmd installfeatures
4. The command can take several minutes to run, please wait

Note: The SharePoint web sites will be inaccessible while the command is running. It is best to run the command after business hours. According to the technet blog article above, the amount of time the command takes to run will vary on the size of the database and the speed of the machine. On a reference machine with 8 logical processors, 32GB of RAM and a 2GB content database, the command took approximately 5 minutes to execute.