Error: The provider returned an unexpected error code.

Hi,
I recently setup a new Hybrid backup and I get the above error after a few seconds of starting the backup. This is directly as the VSS starts.
Things I have tried:
Use system VSS provider in advanced.
Turn off NTFS fast scan
Edit security in the dcomcnfg to make sure system/admins/network service all have full access (This, helpfully, was from logging a ticket - 251033 - via the software, but was told the ticket system is not for free use)
Nothing has worked. It was running fine for a week, but has not ran all week now.
Any ideas?
Thanks in advance

[reply=“Phil Dalton;d1191”] Do you still see event ID 8194 in the event logs? If not, what IDs can be seen there? There’s a lot of info on the net to troubleshoot such problems if you know the event IDs.

No ID 8194, but a lot of 12293. True, there is a lot of info about it, but not much of it is consistent across posts.
While investigating, there seems to be a more general error with VSS / System Protection. Cannot even open the System Protection page. Guess I need to sort that first…
Ah well, joys of Windows…

Well, during investigations, I found Windows 10 build 1903 showing as ready to install, so I installed that.
All is now well, so I guess it was some weird OS issue.
Thanks anyway Matt.