OneDrive Temporary Sync Delay

Dear @Tommy Lok Hei Chan,

Thank you for reaching out to the Microsoft 365 Q&A forum community support team. We understand you are receiving a "temporary sync delay" error regarding your 2.pst file in OneDrive, even after closing Outlook and restarting your computer. 

The error message "High service activity" is often a generic notification triggered when OneDrive cannot bypass a file lock or a sync conflict caused by the way Outlook handles data. 

Important Note: Microsoft officially recommends not storing active or frequently accessed .pst files in folders synced by OneDrive (such as Documents or the OneDrive root). This is because Outlook keeps a constant handle on the file, which prevents OneDrive from uploading changes, leading to performance issues and potential data corruption. 

Please check your Storage again in OneDrive online. 

• Sign in to OneDrive Online in your web browser. 
• Click on the settings in the top right corner, select Options.  
• Click the Manage Storage tab to see if your current storage exceeds 1 TB.  

For more details, please refer to Microsoft’s official documentation: Manage your OneDrive for work or school storage - Microsoft Support 

If you make sure that you have not exceeded the storage space and the problem, there are some possible causes. 

Step 1: Force release the File lock 

Even if Outlook is closed, a background process might still be holding the file. 

1. Right-click the Taskbar and select Task Manager. 
2. Go to the Details tab and look for outlook.exe. 
3. If found, right-click it and select End Task. 
4. Right-click the OneDrive icon (blue cloud) in your system tray, select Pause syncing, wait 30 seconds, and then select Resume syncing. 

Step 2: The "Move and Sync" method 

If the error persists, the sync database for that specific file is likely stuck. 

1. Right-click the OneDrive icon and select Quit OneDrive. 
2. Move the 2.pst file from your OneDrive folder to a local folder that is not synced (e.g., C:\PST_Backups). 
3. Start OneDrive again and let it finish syncing (the error should disappear as the file is gone). 
4. If you need it backed up, upload it to OneDrive via the web browser (onedrive.com) instead of the sync app. 

Step 3: Reset OneDrive (If sync remains stuck) 

If the error message does not clear after moving the file: 

1. Press Windows Key + R. 
2. Copy and paste: %localappdata%\Microsoft\OneDrive\onedrive.exe /reset (If it doesn't work, try other code in the documentation)
3. Press Enter. Then, manually restart OneDrive from your Start menu. 

For more details, please refer to Microsoft’s official documentation:  Reset OneDrive - Microsoft Support 
 

To prevent this from happening again, Microsoft suggests the following workflow for Outlook data files: 

• Keep PSTs Local: Store active PST files on your local drive (e.g., C:\Users\Username\PSTs). 
• When you want to back up a PST to OneDrive, ensure Outlook is closed, then manually copy the file into your OneDrive folder. 
• If you have a Microsoft 365 business subscription, use Online Archiving instead of PST files for a more reliable experience. 

For more details, please refer to Microsoft’s official documentation:  

Restrictions and limitations in OneDrive and SharePoint - Microsoft Support 

How to remove an Outlook .pst data file from OneDrive - Microsoft Support 

Please note that as a forum moderator, I don’t have access to backend tools or internal systems to investigate further, and certain settings or configurations are managed exclusively by your organization’s administrators, so I’m unable to check or make changes on that side. That said, I truly hope these suggestions help you move forward.   

Please let me know if you have any further questions or if the problem persists after trying these solutions. Thank you for your patience and cooperation.

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