Vss error: 0x800423f4

[Vitaliy S.]

Do you have the same issue for all VMs on the host or for some specific ones? Try to look at other VSS related errors in the Windows Event log, maybe they would be more descriptive than the last one.

[Jacv]

I was pulling my hair out with this error for last 3 weeks but managed to fix it last night. I couldn't recreate it consistently as an occasional test restore would just work while others wouldn't - no change to either host or guest so very frustrating. Quite often doing a snapshot of the VM in HyperV manager would allow Veeam to work but deleting that snapshot would fail again - not a long term solution. Veeam support suggested that so that really eased the pressure of no backups.

Host-HyperV 2012R2
Guest-SBS 2011

On the SBS guest, I had VSS error after running following diskshadow commands on system disk (100MB system reserved and 300GB C: partition). Shadow copy snapshots were working on each drive so I didn't think to check diskshadow.

C:\Users\administrator.hosch>diskshadow
Microsoft DiskShadow version 1.0
Copyright (C) 2007 Microsoft Corporation
On computer: SERVER01, 6/04/2016 6:57:34 PM

DISKSHADOW> begin backup

DISKSHADOW> add volume c:

DISKSHADOW> create

COM call "m_pVssBackup->AddToSnapshotSet" failed.

The last operation failed.
- Returned HRESULT: 8004230f
- Error text: VSS_E_UNEXPECTED_PROVIDER_ERROR

DISKSHADOW> end backup

I saw that it was a COM call failure so I restarted "Com+ Event System" service on the guest which restarted about 8 or so services (DHCP server,etc). I then restarted "HyperV volume shadow copy requester" and "volume shadow copy" services. Re-running the diskshadow command then worked fine but the Veeam App aware backup still failed.

On a whim, I tried restarting those 3 services again and not running the diskshadow commands, just the Veeam backup and it worked!

That was last night and it's done 3 backups since.

I really feel for anyone with this error and I can see how there are probably a hundred causes but maybe it can save someone the hours I spent.

[Daithi]

I had similar issues but only when I had "Allow processing of multiple VMs" ticked. When I unticked this my backups worked fine. Just a suggestion for anyone in similar boat.

[pdef]

Update:

I'm still having the same issue. I'm working on this with Veeam and Microsoft Support but we were not able to find any long-term solution yet.

Its a fact that the Backup is able to run successful for few days if the VSS Service has been restarted on the Guest VM. But nevertheless, Error is reoccuring on all of our subsidiary/branch offices.

We have a total of 6 Veeam Installations: 3 of them are using Hyper-V Host and the other 3 are vmWare Clusters. All of the Hyper-V installations are having the same issue since 8 weeks..

Its very frustrating at this time.

[Jacv]

Just to update my post from two weeks ago; backups are still working and no more errors.

Can not explain the sudden failure and then back to consistent success after those service restarts...VSS I guess

[Daithi]

I was getting similar VSS errors now.
Had to restart my VM and move it to another node before Veeam would back it up. Very annoying. I can create snapshots of the VM with no issues on the host itself.

[Vitaliy S.]

I can create snapshots of the VM with no issues on the host itself.

This might not be enough, as VSS snapshot (volume-level) is also triggered by a backup job.

[b_eugene]

I've got this error after vhdx to fix size converting. There is no needed ntfs permissions to new vhdx file or all partition.

[mrhron]

Hi guys.
I was tormented by this problem, but I successfully solved it. In the properties of the virtual machine you need to remove the check mark.
"integration Services" -> "Backup (Volume snapshot)"
After that, the backup was successful.
Good luck.

[ricardo.fonseca]

not working....

:: Guest processing skipped (check guest OS VSS state and hypervisor integration components version)

Any solution?

[foggy]

Hi Ricardo, if you've checked everything mentioned in this thread, please contact technical support for a closer look. Thanks.

[chris1337c]

I had this exact issue, after spending hours digging through event logs, restarting services, moving VM's, running RAID checks, checking for bad blocks, and losing my mind the resolution ended up being very suspect and simple.

I re-created the same VEEAM backup job and disabled the one that caused the VSS writer to fail (I am positive of this and can replicate the issue, open to working with anyone from VEEAM for more clarification into this - Backup & Replication 9.5). I made sure to restart the service on the host/guest machine, and then launched the new backup job.

I hope this post helps someone as this was a weird one.

[Mike Resseler]

Hi Chris,
First: Welcome to the forums!
Second: Thanks for letting us know your solution, but to be honest, it seems a bit strange to me. Recreating the job that fixes a VSS writer that normally fails doesn't make any sense in my mind. So I am going to use your offer for clarification: Can you tell me how you can reproduce this? I will ask QC to see if the same happens

Thanks
Mike

[ExTrAkRaZy]

I have same issue, i solved it:

Start > Services (Start like admin) >

Search SQL Server VSS Writer > Stop

Try it now, works fine 4 me.

Regards.