How to Resolve the “Operation Cannot Be Performed Because the Message Has Been Changed” Error in Outlook?

Ritu Roy | File Repair fix How to's Outlook | 7 minutes read | Modified on: 16-06-2025

If you’re trying to move an email from your Inbox to another folder or attempting to reply to a message, and you encounter the error “The operation cannot be performed because the message has been changed,” it can be both frustrating and disruptive. This issue can interrupt your workflow, delay responses to important emails, and prevent proper mailbox organization.

This guide outlines what causes this error in Outlook and how you can fix it effectively.

Why Does Outlook Show the “Message Has Been Changed” Error?

There are several possible reasons why Outlook might prevent you from performing certain actions on an email, citing that the message has been altered. Below are the common culprits behind this issue:

If you have the same mailbox open in multiple windows or devices, Outlook might detect conflicting actions on the same message, resulting in this error.
Certain third-party add-ins can interfere with how Outlook processes and updates emails. This interference can lead to the message state being flagged as “changed” even when it hasn’t been.
Some antivirus applications scan emails in real time. These scans can trigger changes in the message metadata, causing Outlook to think the email was modified.
Misconfigured settings, especially related to reading panes or message preview, can cause Outlook to treat an email as if it was changed even if no visible modification was made.
A damaged Outlook profile may behave abnormally, causing issues like this error when attempting to move or respond to emails.

In the next steps, you would typically move on to how to fix each cause, starting from disabling add-ins, repairing the Outlook profile, or using the built-in Inbox Repair Tool (SCANPST.EXE) for PST issues.

Solutions to Fix the “Operation Cannot Be Performed Because the Message Has Been Changed” Error in Outlook

Before diving into advanced fixes, make sure that the email you’re trying to move or reply to isn’t open in multiple tabs or windows. If it is, close all duplicate instances and try again. If the issue persists, follow the methods below to resolve it.

Method 1: Temporarily Disable Antivirus or Firewall Software

Sometimes, real-time protection features in antivirus programs or the Windows Firewall may lock or interfere with Outlook’s data files while scanning them. This can prevent normal email operations like moving or replying to messages, which may trigger the “message has been changed” error.

Method 2: Disable or Remove Problematic Add-ins in Outlook

Incompatible or malfunctioning add-ins are a common cause of unexpected behavior in Outlook, including the “message has been changed” error. These third-party extensions can interfere with how Outlook processes and updates emails.

To determine whether add-ins are causing the issue and to remove the problematic one(s), follow the steps below:

Step 1: Launch Outlook in Safe Mode

Close Outlook completely.
Press Windows + R to open the Run dialog box.
Type Outlook /safe and click OK.

If Outlook runs without error in Safe Mode, it means that one or more add-ins are likely the cause.

Step 2: Identify and Disable Add-ins

In Outlook, go to File > Options.
In the Outlook Options window, select Add-ins from the left pane.

At the bottom of the window, locate the Manage drop-down (next to “COM Add-ins”) and click Go.

A list of all installed COM add-ins will appear.
Uncheck all the add-ins to disable them and click OK.

Restart Outlook normally.

Step 3: Isolate the Faulty Add-in

Reopen the Add-ins window using the same steps above.

Enable one add-in at a time, restart Outlook after each, and test whether the error reappears.

Repeat this process until the problematic add-in is identified.

Once found, remove or disable the add-in permanently.

This method helps you pinpoint and remove any conflicting extensions that could be interfering with normal Outlook operations, restoring stability and eliminating the error.

Method 3: Modify Conversation Clean Up Settings in Outlook

Many users have found that adjusting the Conversation Clean Up settings in Outlook can help fix the “Operation cannot be performed because the message has been changed” error. These settings affect how Outlook handles replies and message threads, which may lead to conflicts when trying to move or modify emails.

You can tweak these settings by following the steps below:

Steps to Adjust Conversation Clean Up Options:

Launch Outlook.
Go to File > Options.
In the Outlook Options window, select Mail from the left sidebar.
Scroll down to locate the Conversation Clean Up section.
Uncheck the box labeled:
“When a reply modifies a message, don’t move the original.”

Click OK to save your changes and restart Outlook.

Method 4: Adjust the Save Message Settings in Outlook

Another potential fix for the “The operation cannot be performed because the message has been changed” error is to disable the auto-save feature for unsent items. This setting may unintentionally cause Outlook to treat a message as modified, even if no visible changes were made.

Follow the steps below to turn off this setting:

Steps to Disable Automatic Saving of Unsent Items:

Launch Outlook and click on File > Options.

In the Outlook Options window, select the Mail category from the left panel.
Scroll down to the Save messages section.
Uncheck the box labeled:
“Automatically save items that have not been sent after this many minutes.”

Click OK to apply the changes.
Restart Outlook and check whether the issue has been resolved.

Disabling this auto-save option can help prevent Outlook from mistakenly marking a message as changed while you’re composing or attempting to move it, thus avoiding the error.

Method 5: Repair the Outlook or Microsoft Office Installation

If Outlook continues to display the “The operation cannot be performed because the message has been changed” error, the issue may be due to corrupted installation files within the Microsoft Office suite. Repairing the Office program can help resolve any underlying damage affecting Outlook’s functionality.

Follow these steps to repair your Office installation:

Steps to Repair Microsoft Office:

Press Windows + R to open the Run dialog box.

Type Control and press Enter to open the Control Panel.
Navigate to Programs > Programs and Features.

In the list of installed applications, locate Microsoft Office.
Right-click on it and select Change.

In the dialog that appears, choose the Repair option (you may see Quick Repair and Online Repair; start with Quick Repair first).

Follow the on-screen instructions to complete the repair process.
After the repair finishes, restart your computer and check Outlook to see if the issue is resolved.

Method 6: Set Up a New Outlook Profile

If the “The operation cannot be performed because the message has been changed” error continues to appear, the issue might be related to a corrupted Outlook profile. Creating a fresh profile can help eliminate profile-related corruption and restore normal functionality.

Here’s how you can create a new Outlook profile step by step:

Steps to Create a New Profile in Outlook:

Make sure Outlook is closed completely.
Open the Control Panel (Press Windows + R, type control, and hit Enter).
In the Control Panel window, click on Mail (you might need to switch the view to Small Icons or Large Icons to see it).
In the Mail Setup window, click on Show Profiles.

Click the Add button to create a new Outlook profile.

In the New Profile dialog box, type a name for your new profile and click OK.

Now, in the Add Account window, enter your email account details and click Next.

When prompted, check the “Change account settings” option and continue with the setup.

Once the account is added, go back to the Mail window.
Select your old profile and click Remove (optional, but recommended if it’s not working correctly).
Under “Always use this profile,” select the new profile you just created from the dropdown.
Click Apply and then OK.

After this, launch Outlook using the newly created profile and check if the error has been resolved. A new profile ensures a clean environment, free from existing corruption or misconfigurations that may be causing the issue.

Method 7: Fix Corrupt Outlook PST File Using SCANPST or a Professional Tool

If you’re encountering the “The operation cannot be performed because the message has been changed” error while replying to or moving an email in Outlook, it may be due to corruption in the PST file, the primary data file Outlook uses to store your emails, contacts, calendar entries, and more.

#1: Use Outlook’s Built-in Repair Utility (SCANPST.exe)

Outlook includes a default repair tool called Inbox Repair Tool (SCANPST.exe) that scans and fixes minor corruption issues in PST files.

Steps to Use SCANPST:

Exit Microsoft Outlook.
Open the Run dialog by pressing Windows + R and type the path to SCANPST.exe (usually located in your Outlook or Office installation folder).
Click Browse and select the PST file you want to repair.
Click Start to begin scanning.
If any issues are found, click Repair to fix them.

Note: The time it takes will depend on the file size and how badly the file is corrupted.

# 2: Use a Professional PST Repair & Conversion Tool

If SCANPST.exe fails to fix the file, especially in cases of severe corruption or a large/encrypted PST file, a more advanced solution is recommended. A tool like Outlook Converter is ideal for this scenario. Offers export options to various formats and platforms, such as: PDF, DOC, EML, MBOX, MSG, HTML, XPS, JPEG, BMP, SVG, vCard, CSV, ICS, Office 365, Gmail, G Suite, Yahoo Mail, IMAP, Amazon WorkMail, Outlook for Mac (OLM), Thunderbird, Zimbra, Lotus Notes, Windows Live Mail, and many more.

Conclusion

The Outlook error “The operation cannot be performed because the message has been changed” typically occurs when trying to move or reply to a message and is often caused by issues such as add-ins, profile corruption, or data file damage. This guide walked you through multiple troubleshooting steps, from disabling add-ins and adjusting settings to repairing data files.

If built-in tools like SCANPST.exe don’t resolve the problem, an advanced tool like the CubexSoft PST File Converter can help repair and restore access to your data while offering flexible export options.