How to Fix Outlook Error 0x80070021 During PST File Backup

IT professionals and Microsoft Outlook users often copy their PST files to create backups. But sometimes they encounter the Outlook Error 0x80070021 with the message “The process cannot access the file because another process has locked a portion of the file.” This generally happens when the required PST file is in use, or Outlook is running in the background. This article explains the causes, manual solutions, and the use of the Aryson Outlook PST Repair Tool to achieve a secure and quick conversion. Download Now   Purchase Now

Symptoms of Outlook PST Backup Error 0x80070021

There are a number of problems that might occur when the Outlook PST backup error 0x80070021 appears. Given below are some of the common symptoms.

  • Users may see the error message when they try to copy the Outlook PST file.

“The process cannot access the file because another process has locked a portion of the file.”

  • The Outlook PST file may fail to copy to another folder or storage device.
  • Even after closing Outlook, the PST file may remain locked or inaccessible.
  • Furthermore, users become unable to move PST files to external drives.
  • The Outlook data file backup process may stop unexpectedly.

What Causes Outlook Error 0x80070021?

It is important to understand the root cause of the error 0x80070021 before proceeding to the methods of migration.

  1. A PST file might get locked if Outlook is running in the background.
  2. Antivirus or security software may scan the PST file during backup.
  3. Moreover, the Windows search indexing service may access PST for indexing emails.
  4. Cloud synchronization tools like OneDrive may continuously sync the PST file.
  5. Furthermore, the Outlook add-ins may keep the PST file active.
  6. The file access conflicts may occur due to the PST files stored on network drives.

Now, from the above causes, identify the reason you are facing the error 0x80070021 Outlook PST file. Refer to the following solutions and choose the appropriate method to fix Outlook Error 0x80070021.

How to Fix Error 0x80070021 When Taking PST Backup?

In this section, we will mainly focus on the most effective solutions to resolve the Outlook PST file backup error.

  • Close Outlook Background Processes
  • Disable Outlook Add-ins
  • Stop Windows Search Indexing
  • Using an Advanced Software

Read through each of these methods carefully and apply them according to the cause of the problem. If manual methods do not resolve the issue, you can use the automated solution discussed below.

Fix 1: Close the Outlook Processes Running in the Background

Sometimes, even if you close Outlook, it continues running in the background. As soon as any Outlook process remains active, the PST file will remain locked and cannot be copied or backed up. Therefore, it is important to close all Outlook-related processes before taking a backup.

Steps to Close Outlook Background Processes

  1. Firstly, close the Microsoft Outlook application on your system.
  2. After that, press Ctrl + Shift + Esc keys to open the Task Manager.
  3. Next, browse the OUTLOOK.EXE in the list of running processes.
  4. Now, select the required process & click on End Task.
  5. Make sure to check for related applications like Skype or Lync and close them.
  6. At last, try to copy the PST file again to create the backup.

Fix 2: Disable Outlook Add-ins

Even a third-party Outlook add-in may interfere with the PST file and prevent it from being copied. Once you disable any unnecessary add-ins, it will release the locked PST file, and hence, the Outlook Error 0x80070021 will be resolved.

Steps to Disable Outlook Add-ins

  1. Firstly, use the Windows + R shortcut key to open the Run dialog box.
  2. After that, type Outlook.exe /safe and open Outlook in Safe Mode.
  3. Next, navigate to the File tab >> Options >> Add-ins.
  4. Now, click on Manage COM Add-ins & select Go.
  5. Uncheck all unnecessary add-ins and click OK.
  6. Restart Outlook normally and try taking the PST backup again.

Fix 3: Disable Windows Search Indexing

Windows search indexing scans Outlook data files to index emails to achieve quick search results. During this process, the PST file may become locked, which prevents users from copying it. This issue can be resolved once you disable the indexing temporarily.

Steps to Stop Windows Search Indexing

  1. Firstly, open the Control Panel on your existing system.
  2. After that, click on Indexing Options.
  3. Next, click Modify to change the indexed locations.
  4. Now, remove the Outlook PST file location from indexing.
  5. Apply the required changes & restart your system.
  6. At last, attempt to copy the PST file again.

Fix 4: Advanced Software to Fix Outlook Error 0x80070021

Aryson Outlook PST Repair Tool is one of the most reliable solutions that can repair corrupted Outlook PST files within a few clicks. It aims to recover emails, contacts, calendars, notes, and attachments without affecting the original formatting or structure. Moreover, IT professionals use this software to scan PST files of different levels of corruption. Additionally, it can scan severely corrupted, large-sized, and password-protected PST files, which makes it a suitable choice for both individual users and organizations. Furthermore, this software can be used to repair corrupted Outlook PST files without scanpst. Also, the software allows users to preview the selected PST files before the recovery begins.

Simple Steps to Resolve Outlook PST File Access Denied Error

  1. Install the Aryson Outlook Repair Tool on your current system.
  2. Then, click on Open to load the required Outlook PST file from your computer.
  3. Choose a desired recovery mode: Standard, Advanced & Deep Mode.
  4. Then, choose between the Outlook 32-bit or 64-bit versions, & click OK.
  5. Select the required items of the PST file & cross-verify them.
  6. Choose the output format & apply the required filters if needed.
  7. At last, provide a particular location for the recovered PST file.

Conclusion

In this blog, we discussed some of the possible reasons why the Outlook error 0x80070021 takes place. Along with that, we explored several manual methods to resolve the error 0x80070021 and learned the use of advanced software. If manual methods work for you, proceed with them. But in case none of them works well, opt for the automated solution, as the issue might be residing in your PST file itself. In case of any doubts, reach out to the tech support team at Aryson.

FAQs

Q1. What is Outlook error 0x80070021?

Ans: Outlook error 0x80070021 occurs when another process locks the PST file and prevents users from copying or backing it up.

Q2. Why does the PST file fail to copy during backup?

Ans: The PST file may be locked by Outlook, antivirus software, indexing services, or cloud synchronization tools.

Q3. How can I unlock a PST file in Outlook?

Ans: With the help of the Aryson Outlook PST Repair Tool, you can unlock a PST file in Outlook.

Q4. Can antivirus software cause PST backup errors?

Ans: Yes, antivirus scanning may temporarily lock the PST file and prevent backup operations.

Q5. Can corrupted PST files be repaired?

Ans: Yes, corrupted PST files can be repaired using professional PST recovery software.

5/5 - (2 votes)

About The Author:

Rohan Wiese is a Technical Writer at Aryson Technologies. He is an expert Email Forensic, Cloud Computing, and a passionate nerd with over 10 years of experience in technical content writing. He writes about Cloud Migration, Database Recovery, Email Backup, Windows, Mac, and Tech.

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