Outlook offers a comprehensive array of functions for organizing contacts, projects, emails, and calendars. Its variety of use cases allow it to help people and businesses improve productivity and communication processes.

It can, however, encounter issues akin to those seen by other programs, which could impede communication. The error code 0x80070021 is among the most frequent ones that Outlook users encounter. It arises when you try to copy a PST file from one location to another, and it commonly shows as:

“An unexpected error is preventing you from copying the file. If you continue to experience this error, you can utilize the error code to seek assistance for this issue.

Error 0x80070021:The process cannot access the file because another process has blocked a portion of the file.”

Before we dive into the solutions, let’s get to the bottom and ‘dot i’s and cross t’s’ on the reasons.

What are the Reasons for Outlook Error Code 0x80070021?

1. Outdated Outlook
2. Conflicting applications running in the background
3. Software or hardware issues
4. Power outage
5. Corrupt data storage device
6. Network device failure
7. Locked PST file
8. Faulty add-ins

Ways to Fix Outlook Error Code 0x80070021:

Follow various methods mentioned in our step-by-step guide to troubleshoot and resolve Outlook error 0x80070021:

1. Update Outlook

It’s critical to keep Outlook updated in order to get access to the most recent enhancements and bug fixes. Make sure you are running the most recent version of Outlook. To fix any flaws or difficulties causing the error, check for updates and install them.

• Navigate to the ‘File’ tab after opening Outlook to update the program
• Depending on the version you are using, choose ‘Account’ or ‘Office Account’
• Choose ‘Update Now’ from the ‘Update Options’ menu to find and install any available updates

2. Perform a Clean Boot

As previously mentioned, if another software is utilizing the file, it may result in the error 0x80070021. Therefore, users have the option of performing a clean boot to ensure that minimum applications are operating for resolving Outlook 0x80070021 error code.

• To launch the Run dialog, simultaneously press the ‘Windows’ and ‘R’ keys. Type ‘msconfig’ into the box and choose ‘OK’ to proceed.
• Select the ‘Services’ tab in the pop-up window, check the box next to ‘Hide all Microsoft services,’ and then select ‘Disable all’
• Next, select ‘Open Task Manager’ from the ‘Startup’ menu
• As you can see, this list contains many startup items. To proceed, choose items that are not needed and select ‘Disable.’
• After completing all the procedures, reopen the Outlook file and verify if the problem 0x80070021 has been resolved.

3. Close Outlook using Task Manager

Error 0x80070021 may occur when Outlook continues to operate in the background even after it has been closed. Thus, to resolve the Outlook error 0x80070021, consider shutting down Outlook and see whether it resolves the problem. Follow the below instructions:

• Close Outlook
• Press ‘CTRL’ + ‘ALT’ + ‘DEL’ and select Outlook from ‘Processes’
• Alternatively, you can right-click on the ‘Taskbar’ and select ‘Task Manager’ from the context menu. Scroll down to locate Outlook under ‘Processes.’
• Next, to proceed, select ‘Outlook’ and choose ‘End task’
• Once it’s done, try managing or copying Outlook data files to see if the problem 0x80070021 has been resolved.

4. Remove Search Email Indexer

Another cause of error 0x80070021 is that the COM Add-in is not accessible by the process, which might keep Outlook from shutting down entirely. That implies that even when Outlook is closed, it continues to run in the background. Thus, remove the COM Add-in that may be causing the 0x80070021 issue.

• Open Outlook on your computer
• Navigate to ‘File’ > ‘Options’ > ‘Add-ins’
• Choose ‘COM Add-ins’ from the list by scrolling down and clicking the ‘Manage’ button. View the list of ‘add-ins’ that are installed.
• Ultimately, choose the ‘Search Email Indexer’ and click to entirely remove it
• Open Outlook now to see if the Windows 10 problem 0x80070021 has been resolved

5. Restart into Safe Mode

You have the option of starting the machine in Safe Mode to resolve the issue 0x80070021.

• To launch the Run dialog box, press the ‘Windows’ and ‘R’ keys simultaneously. Type ‘msconfig’ into the window and choose ‘OK’ to proceed.
• Select the ‘Boot’ tab in the pop-up box
• Next, make sure the ‘Safe boot’ is checked. After that, Safe Mode will be booted up on your computer.
• After your system enters safe mode, check Outlook files and verify if the issue 0x80070021 has been resolved

6. Take Microsoft Office Communicator off the Computer

Another possibility for the issue 0x80070021 is if your machine has a Microsoft Office Communicator installed. The Microsoft Office Communicator can be uninstalled in this case.

• In Windows’ search box, type ‘Control Panel,’ then select it
• Under the program section, choose ‘Uninstall a program’ to proceed
• When the Microsoft Office Communicator pops up, choose it and give it a right-click. And to proceed, select ‘Uninstall.’

After uninstalling Microsoft Office Communicator, try managing Outlook files again to see if the issue 0x80070021 has been resolved.

7. Use Outlook PST Repair Tool

Stellar Repair for Outlook is one such PST repair program that might be useful when dealing with the error code 0x80070021 in Microsoft Outlook. Here are some details on how to fix the problem with this tool:

• Download and install the tool: To begin, go to the official Stellar Repair for Outlook website and download the software. Install the program on your PC after downloading it.
• Start the application: Stellar Repair for Outlook should be launched upon installation. The primary interface will appear with choices for choosing the PST file that needs repair.
• Choose and scan the PST file: Select the corrupted or damaged PST file that is giving error 0x80070021 by clicking on the ‘Select Outlook Data File:’ option. Next, to begin the scanning process, click the ‘Repair’ option.
• Repair the PST File: The program will start by inspecting the chosen PST file to find any corruption or errors. A preview of the repaired items will be shown when the scan is finished.
• Save the repaired PST file: Select ‘Save Repaired File’ after making sure the repaired items are intact. You may save the repaired file in PST, MSG, EML, RTF, HTML, and PDF formats with Stellar Repair for Outlook.
• Choose ‘Select Destination’ to store the PST file in a desired location and click ‘OK’.
• Import the repaired PST file in Outlook: Click the ‘File’ tab after opening Microsoft Outlook. Next, choose ‘Open’ > ‘Import’ and then ‘Outlook Data File’ in ‘Import a File’ dialog box. Navigate to and choose the previously saved, repaired PST file. By doing this, Outlook will import the PST file that has been repaired.
• Try the functionality of Outlook: Check to see whether the issue code 0x80070021 is fixed after restarting Outlook. You should now be able to view the repaired PST file without any problems.

Conclusion:

Although Outlook error 0x80070021 might be bothersome, you can diagnose and fix the problem completely by using the methods listed above. Don’t forget to often backup your Outlook data to prevent losing it in the event of corruption or mistakes. If the issue leads to data loss, you might want to try resorting to PST repair tools for additional help.