Hi @Manohar
Do you use OneDrive to sync SharePoint Server?
Please check whether you can sign into OneDrive Online.
It's recommended to go to local OneDrive folder, check OneDrive icons beside with files.
If there is any files with red cross, please move it out of OneDrive folder.
Then I suggest you unlink account, close onedrive and relink it for testing, check whether files can be downloaded or synced again.
If it does not help, I would suggest you uninstall it, reboot your machine to install it.
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