Fix Error 0x80070021: Another Process is Locking a File Portion

Key Notes

  • This error commonly occurs due to background processes locking the PST file.
  • Launching Outlook in Safe Mode helps to identify conflicting add-ins.
  • Performing a Clean Boot can isolate the cause of the error.

Resolving Error 0x80070021 in Microsoft Outlook: Your Complete Guide

Encountering Error 0x80070021 while trying to export your PST file in Microsoft Outlook can be frustrating. This detailed guide provides practical solutions to troubleshoot this error and restore your functionality.

Troubleshooting Error 0x80070021

Step 1: Verify Background Processes

Even if you have closed Outlook, it may still be running in the background. This could lead to the “Error 0x80070021”.To ensure it is not running:

  • Open the Task Manager.
  • Under the Processes tab, locate Outlook, and click the End Task button.
  • If Outlook is absent from Apps, check Background processes and end it if found there.

Pro Tip: Always refresh the Task Manager to update running processes before proceeding.

Step 2: Open Outlook in Safe Mode

Conflicting add-ins might trigger this error. Launch Outlook in Safe Mode to determine if this is the case:

  • Exit Outlook and re-launch while holding the Ctrl key.
  • Check if the error persists when using Safe Mode. If the error is resolved, an add-in is likely causing the issue.
  • To identify the problematic add-in, exit Safe Mode and open Outlook normally. Navigate to File > Options > Add-Ins.
  • Select COM Add-ins and click GO. Uncheck any add-in to disable it, then check if the error continues.

Step 3: Disconnect from the Internet

Try disconnecting from the internet and then opening Outlook:

  • Turn off your Wi-Fi or enable Airplane Mode.
  • Attempt to save the PST file while offline.

Step 4: Conduct a Clean Boot

A Clean Boot starts Windows with a minimal set of drivers and startup programs, which help in identifying the cause of the error:

  • Press Windows + R and type msconfig, then hit Enter.
  • Select the Services tab, check Hide all Microsoft services, and click Disable all.
  • Go to the Startup tab, and click Open Task Manager to disable all startup items.
  • Restart your computer and try to open Outlook.

Pro Tip: Enable services and startup items one by one to find the specific application causing the issue.

Step 5: Manually Copy the PST File

If other steps don’t resolve the error, manually copying the PST file might help:

  • Open Outlook, navigate to File > Account Settings > Account Settings.
  • Click on the Data Files tab to find the path of your PST file.
  • Close Outlook. Use File Explorer to access that location and copy the PST file to a new location.

Additional Tips

  • Ensure Outlook is updated to the latest version.
  • Check for third-party application conflicts that could interfere with Outlook’s operations.
  • Consider running a repair on your Office installation if errors persist.

Summary

Fixing Error 0x80070021 in Microsoft Outlook requires verifying background processes, running Outlook in Safe Mode, disconnecting from the internet, performing a Clean Boot, and considering manual PST file manipulation. These steps can help restore normal functionality to Outlook, allowing users to export their PST files successfully.

Conclusion

Following these troubleshooting steps can help you effectively mitigate the “Error 0x80070021” issue in Outlook. If errors persist, it might be beneficial to consult Microsoft’s support or community forums for further guidance.

FAQ (Frequently Asked Questions)

What could cause error code 0x80070021?

This error typically arises due to background processes or add-ins preventing access to the PST file.

How can I prevent this error in the future?

Regularly update Outlook, manage your add-ins, and ensure your PST files are backed up properly to minimize these issues.