Hi Laura Jennings,
I understand how confusing and frustrating it can be when files are duplicated without any clear reason.
The next step is to confirm whether the duplicates are actually being created by OneDrive or by another application.
Please check whether the affected files are stored inside a OneDrive folder and whether the duplicate filenames include the name of your computer. If the computer name is added, the issue is usually related to OneDrive synchronization. Since you have already refreshed the credentials, check whether the same folder is being synced or backed up from another device, and avoid editing the same file on multiple devices at the same time.
You can also try resetting the OneDrive sync connection by pressing Windows key + R, entering:
%localappdata%\Microsoft\OneDrive\OneDrive.exe /reset
Then reopen OneDrive from the Start menu. Resetting OneDrive should not delete the files stored in the cloud.
If the duplicates are outside OneDrive or do not include the device name, please share the folder location and an example of how the duplicate filenames appear. That information will help identify whether OneDrive, another backup service, or a specific application is creating them. Thank you so much for your understanding.
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