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Hi
On Windows 10, Volume Shadow Copy Service was working perfectly because I had system restore points but more importantly I had Macrium Reflect using shadow copies to create images and SyncBack was able to use the shadow copy to copy busy files like PSTs. After Windows 11 update, the Volume Shadow Copy Service no longer works and running CMD commands like "vssadmin list writers" shows no errors and all "state 1 stable". There is also only one "writer" as always.
Attempting to "open system restore" shows this error
...and the event log:
Volume Shadow Copy Service error: Unexpected error IOCTL Unpack overflow. hr = 0x8000ffff, Catastrophic failure
Volume Shadow Copy Service error: Unexpected error calling routine Output buffer overflow. Reading bad arguments. dwSize = 8. hr = 0x8000ffff, Catastrophic failure
As I now have no Macrium images going through this is a priority for me to solve so help appreciated.
Thanks
Mike
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So it seems a 3rd party drive pool product I was using released a beta to help with Win11 compatibility and it is somehow breaking the Shadow Copy service (ie no restore point possible). Removed this product and Restore Points again possible.
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Type ‘services.msc’ in the empty field of the Run box and hit the Enter key.
find ‘Volume Shadow Copy’ entry.
When found, double-click the entry.
Set the Startup type to ‘Automatic (Delayed Start)’ and click the Start button below it.
Also configure the Startup type for ‘Microsoft Software Shadow Copy Provider’ to Automatic (Delayed Start) and Start the service.
Perform a Clean Boot and then try to run the operation you want.
Thanks but I already have that set. Also it should be known I have already also done:
...so the disk C is fine and Windows needs no repair according to point 2+3.
also re-registered the services before posting this ticket.
C drive has also been "cleaned" including system files using normal "Properties->Tools" tab and registry cleaned (only after all above failed).
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Readers / viewers may benefit from viewing the name of the third party software.
I would but in this era of quick litigation, I'm reluctant to name it. There really are maybe 3 Windows Drive Pool applications out there so expect all 3 to cause a problem. I can say that I have switched to StableBit DrivePool and it is working 100%.
