I have a server running Windows 2012 R2. Since the installation of Windows 2012 R2 Update 1 (KB2919355), the VSS System Writer is missing. When using "vssadmin list writers" from command prompt, the following error is displayed in the event log:
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Log Name: Application
Source: Microsoft-Windows-CAPI2
Date: 28/08/2014 21:35:28
Event ID: 513
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: Server-RDS.domain.local
Description:
Cryptographic Services failed while processing the OnIdentity() call in the System Writer Object.
Details:
AddCoreCsiFiles : RtlConvertNtFilePathToWin32Path() failed.
System Error:
0xC0000039 (unresolvable).
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The server is not able to take a VSS snapshot during a backup which is a cause for concern. Most forums suggest resetting permissions on the %windir%\winsxs\filemaps\ directory, which I have tried but does not resolve the issue. I restored the server to the point before Update 1 was installed and the system writer was present, however as soon as Windows 2012 R2 Update 1 was installed, the writer no longer exists. The only difference to this server compared to other Windows 2012 R2 servers which I have deployed (and Update 1 has installed no problems with no VSS writer issues), is that the user profiles have been moved to a different volume. I suspect this is a permissions problems and although I have tried running the Sysinternals Process Monitor, I cannot see any permission problems when the VSS writers are called.
Does anyone have any suggestions. Thanks in advance.
