"Last week OneDrive silently rolled back two of my files, one Excel, one PowerPoint. [...]
This is NOT a Sync issue between machines. I have one machine connecting to one OneDrive account."
Thanks for posting this. Using only one PC and having the same issue is indeed new information.
that could be of use to someone trying to determine the cause of the problem--IF such a person exists.
I had a similar problem around New Years Day. Multiple files that I update (from multiple computers) on a weekly, or monthly, or random schedule, were suddenly missing all information that I had added since October. Let me restate that for the doubting Thomas moderator: these files were not all opened on the same PC on the same day and somehow subject to a single user-initiated error. Some hadn't been opened for weeks since they were last updated, and yet they all reverted to the October timeframe. And version history was no help--it showed no versions with data newer than October, even though I update two of the files every week. Luckily, I'd made a backup of one of my systems on Christmas Day, so I could revert to an "older," but more updated version.
Like others here, my faith in OneDrive is shaken. I've had a 365 Family subscription for maybe 5 years now, and never doubted that I was covered because I could ALWAYS revert to an older version and be almost up to date. Now I know that not only am I not "covered" by OneDrive, but I may actually be sabotaged by OneDrive. OneDrive was supposed to be a way to avoid losing work, not the reason work was lost. But, of course, it must be my fault.
P.S. Today I opened an Excel file that I was puzzled to see showed a "Date modified" of August 11, even though I was sure I had added to it since then (it's a record of vehicle maintenance for 4 vehicles). Inside there were entries from December, as I had "remembered", but the "Date modified" says August 11. How does that work? The General tab of File properties also shows a Modified date of August 11, 2024 but the Details tab shows a Date last saved of December 13, 2024. So a Save isn't a Modification. Oh, I see, back in August I must have entered the odometer readings and the cost for maintenance that was to be performed up through December, then I must have opened the file in December and saved it without modifying it. Yes, that all makes sense. It is my fault again.