This is the MS guide for VSS on Windows Server 2003 - 
http://support.microsoft.com/kb/826936 - Your specific error message is 
mentioned "error=0x800423f4"
With Windows 2003, you also have the option of setting the client Save 
Operation to "VSS:*=off".  This will not use VSS and skip locked 'in use' files.

I've also come across a handy VSS writers reset which can be batched:

"vssadmin list writers" will show you the state of any VSS-aware applications. 
If any of them are in a bad state (a state other than Stable) then you will 
need to manually reset the writers' states. To reset VSS writer states, run 
these commands on the command line:

32Bit Windows Server 2003 VSS Reset:
net stop vss
net stop swprv
cd %SystemRoot%\system32
regsvr32 ole32.dll
regsvr32 vss_ps.dll
Vssvc /Register
regsvr32 /i swprv.dll
regsvr32 /i eventcls.dll
regsvr32 es.dll
regsvr32 stdprov.dll
regsvr32 msxml.dll
regsvr32 msxml2.dll
regsvr32 msxml3.dll

64BIT adjustment:

net stop vss
net stop swprv
cd %SystemRoot%\system32
regsvr32 ole32.dll
regsvr32 vss_ps.dll
Vssvc /Register
regsvr32 /i swprv.dll
regsvr32 /i eventcls.dll
regsvr32 es.dll
regsvr32 stdprov.dll
cd %SystemRoot%\SysWOW64
regsvr32 msxml.dll
regsvr32 msxml2.dll
cd %SystemRoot%\system32
regsvr32 msxml3.dll
regsvr32 vssui.dll




emcuser wrote:
> I've been having intermittent backup issues using Networker 7.4.4 while 
> backing up the VSS System Boot saveset of a Windows 2003 SP2 32 bit server. 
> It fails with the following error message:
> 
> servername:VSS SYSTEM BOOT:\ 1 retry attempted
> servername:VSS SYSTEM BOOT:\ 5388:(pid 6304): Failure status of writer 
> Registry Writer - VSS_WS_FAILED_AT_PREPARE_SNAPSHOT
> servername:VSS SYSTEM BOOT:\ VSS SYSTEM BOOT: ERROR: VSS failed to process 
> snapshot, error=0x800423f4: The VSS writer operation failed because of an 
> error that might recur if another shadow copy is created. ** Says to look on 
> Event and Error help link.
> servername:VSS SYSTEM BOOT:\ 7162:(pid 6304): save of VSS SYSTEM BOOT:\ to 
> servername failed
>  
> So far the only fix is to reboot the server. Any help would be 
> appreciated.[/b]


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