Sync error on Onedrive

When a large number of synced files are deleted at once, OneDrive can pause the operation and ask you to confirm that the deletion was intentional. Since the message has remained for six weeks, I would first verify the actual state of the files before resetting anything:

1. Sign in to OneDrive.com using the same Microsoft account.
2. Open Recycle bin and check whether the files you intentionally deleted are there. Do not empty the Recycle Bin until you are sure there is nothing you need to recover. Personal OneDrive items are normally retained in the online Recycle Bin for 30 days, although items that have already been permanently deleted cannot be recovered.
3. Also check a few folders in OneDrive.com to make sure the files you want to keep are present.

If everything looks correct online and only the OneDrive Windows application continues showing the old error, reset the OneDrive sync client. Press Windows + R, paste:

%localappdata%\Microsoft\OneDrive\OneDrive.exe /reset

and press Enter.

If Windows says it cannot find OneDrive, try:

C:\Program Files\Microsoft OneDrive\OneDrive.exe /reset