A Microsoft file hosting and synchronization service.
Hi, Vox Populi
It is understandable to be concerned, especially when important files are disappearing. “System account” is usually an automated service entry and does not, by itself, identify what caused the deletion. A synced device, shared-folder access, or unwanted software may still be triggering the changes.
Here are some suggestions you can try:
Pause OneDrive syncing on every connected computer or mobile device so additional deletions do not sync to the cloud.
Sign in to OneDrive on the web and open Recycle bin. Select the missing files, then choose Restore. Also check the Windows Recycle Bin. Cloud-only files may appear only in the online OneDrive Recycle Bin.
If many files were deleted, open Settings > Options > Restore your OneDrive and select a time before the deletions began. Microsoft 365 subscribers can undo file activity from the previous 30 days. Review the activity list carefully before restoring.
Change the Microsoft account password, review recent sign-in activity, remove unfamiliar devices, and run a full Windows Security scan before resuming sync.
Thank you for your patience in reading, I hope this information has been helpful to you.
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