Hi @Michael Kennett ,
Please try below methods and see the outcomes.
Method1:
“Upload Failed” error message the most popular fix for this problem is to go into OneDrive settings (right-click the little cloud icon to the right of the taskbar and choose Settings). Then find the Office tab and uncheck "Use Office to sync Office files that I open".
Method2:
Right click the icon of Microsoft Office Upload Center in the system tray, and select Settings. Then click Deleted cached files under Cache Settings.
Method3:
Clear the Windows credentials. Open Control Panel>User Account>Credentials Manager>Windows Credentials>Delete all MicrosoftOffice16 and MicrosoftOffice15 credentials.
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