A Microsoft file hosting and synchronization service.
The “server is too busy” message is commonly temporary, so first protect the unsynced file, wait a few minutes, and retry after checking whether OneDrive is experiencing a service issue.^1^
Check whether it is OneDrive or your PC
- Save a separate local copy first
- In the Office application, select File > Save As > This PC and use a new filename.
- Do not discard the pending version until it appears on OneDrive.com.
- Check OneDrive service status
- Open Microsoft’s public Service Health portal and look for a OneDrive or Microsoft 365 incident.
- If an incident is listed, retain the local copy and retry after the incident is resolved. Microsoft publishes current OneDrive issues and workarounds on its support page.^2^
- Test a small file on the OneDrive website
- Sign in to OneDrive.com.
- Upload a small text file to My files.
- If that also fails: the issue is likely account-, storage-, or service-related.
- If it succeeds: the Windows OneDrive app or the original file is the likely scope. Microsoft provides separate troubleshooting for website uploads.^3^
If website upload also fails
- Check your available OneDrive storage. When Microsoft storage is exceeded, OneDrive cannot upload, edit, or synchronize new files.^4^
- Try another small file. Failure of only one file points to that file rather than the whole account.
- If storage is available and no service incident is shown, use Contact Microsoft Support from the Personal accounts section of Microsoft’s OneDrive troubleshooting page.^4^
If website upload works
- Select the OneDrive cloud icon near the Windows clock.
- Check whether synchronization is paused or whether a particular file is listed as an error.
- Close the affected Office file completely.
- Move the affected file out of the OneDrive folder to a local folder, wait for OneDrive to finish processing, and then move a copy back into OneDrive.
- If a folder remains pending without showing an affected file:
- In File Explorer, select View > Show > Hidden items.
- Look for a hidden or
.TMPfile. - Do not delete a
.TMPfile unless it is no longer needed; it can contain unsaved application work. Microsoft also recommends creating a new folder, copying the visible files into it, and deleting the old pending folder when no hidden file is responsible.[^5^](https://support.microsoft.com/onedrive/onedrive-is-stuck-on-sync-pending#onedrive-folder-shows-sync-pending-but-no-file-is-visible "OneDrive is stuck on "Sync pending" | Microsoft Support")
If the OneDrive taskbar icon itself remains stuck on “Sync pending,” follow Microsoft’s linked procedure to delete the Office Document Cache. This branch applies to the toolbar/client status, not merely one pending file.[^5^](https://support.microsoft.com/onedrive/onedrive-is-stuck-on-sync-pending#onedrive-folder-shows-sync-pending-but-no-file-is-visible "OneDrive is stuck on "Sync pending" | Microsoft Support")
Last client-side fallback
If every file uploads through the website but none uploads through File Explorer:
- Select the OneDrive cloud icon in the notification area.
- Select Help & Settings > Settings > Account.
- Select Unlink this PC, then Unlink account.
- Start OneDrive, sign in with the same personal Microsoft account, and select the existing OneDrive folder when prompted.
Unlinking does not delete files already stored online, but keep the separate local copy of anything still pending. Microsoft lists unlinking and relinking as a supported fallback for persistent synchronization problems.^4^
References