Outlook Crashing When Replying to Email with Attachments

  

Rollins Duke   
Published: October 14th, 2025 • 8 Min Read

Hello Readers, As we have received lots of queries about Outlook crashing. After lots of research we are back with the best solution to fix this. As study by TRG DataCenters showed Outlook had a major outage over a recent year which impacted hundreds of millions of users globally.

When users say Outlook is crashing, they’re referring to sudden freezes, forced closure, or complete application failures while performing everyday tasks. These crashes can interrupt important work, delay communication and sometimes lead to data loss if emails or attachments aren’t saved properly.

Helpful Data Point

Common Scenarios of Outlook Crashing

• Outlook may freeze or close while replying due to cached data, add-in conflict or sync errors.
• Crashes mostly happen when replying or attaching large files. Damaged attachments or antivirus can be the reasons for Outlook crashing.
• Users on Reddit and Microsoft community often asked about Outlook crashing when replying with attachment usually in update or using New Outlook interface.
• This happens during send/receive operations when Outlook mailbox fill or become large.
• Crashing when accessing calendar events to shared calendars due to damaged Outlook data or sync issues.
• Outlook may crash when using integrated To Do feature, typically from syncing or task-data corruption.
• Recent updates or incompatible add-ins can also be the reason for Outlook crashing. A repair or fully update usually fixes these issues.

How to Fix Outlook Crashing Manually?

Method 1. Outlook Crashing When Replying Email

1. First, open Outlook and click on help.
2. Tap for Check for Updates and Install latest version.
   
3. Hit on File and press on Options.
   
4. Select Add-ins and Manage COM:Add-ins and uncheck All.
   
5. Restart Outlook.
6. Windows: Open Control Panel and hit on Mail(Microsoft Outlook).
   
7. Click on Show Profiles and hit on Add.
   
8. Press on Configure your Account and set it as default.
9. Mac: Outlook-preferences- Accounts and press on Re-add Account.

Method 2. Outlook Crashing When Replying With Attachments

1. Open the email and hit on Remove Attachments and try replying again.
2. Save Attachment locally and click on Reopen Individually and hit on Delete damaged files.
3. Windows: Close Outlook and Navigate to %localappdata%\Microsoft\Outlook and press on Delete OST file.

Method 3. Reply to Email with Attachments Crashing Outlook

1. Press Win+R and type Outlook/safe and press Enter.
   
2. Mac: Hold option while launching Outlook.
3. Reply with Add-ins : Safe Mode disable add-ins automatically, attempt reply.

Method 4. Outlook Crashing When Sending or Receive Emails

1. Archive old emails and move large attachments to local storage.
2. Click on file and hit on Account Settings then tap on Repair.
   
3. Tap on Test Account.
4. Use ScanPST to repair OST/PST files.

Method 5. Outlook Crashing When Opening Calendar or Switching Views

1. Click on file and tap on options and choose Calendar.
2. Clear Cache files.

Method 6. To Do Crashing When Using New Outlook Interface

1. Click on Tools and hit on Accounts and choose Account.
2. Select Advanced and reset.
3. Remove Account and Add Account Again.
4. Disable Faulty Add-ins.

Method 7. Random or Frequent Outlook Crashes After Update

1. Check for pending updates and press Install.
2. Choose Relaunch Outlook.
3. Click on Safe Mode launch and hit on Test if crash persists.

Benefits of Automated Methods

• This software can repair a batch number of corrupted Outlook PST files.
• It offers a simple initiative interface to make it friendly for all types of professional and individual users.
• You can also save and repair Outlook PST files and can also export PST to PDF, MSG, EML, MBOX and many more.
• With this software, you can also use filter options, use PST filter, separate PST per user, split PST file, and ignore system hierarchy.
• This software offers dual mode to easily select any files from nested folders or can select batch Outlook PST files.

Advanced Fixes

Solution 1. Reset Outlook Setting to Default

1. On Windows: Close Outlook and press Win+R.
2. Type Outlook.exe/resetnavpane and hit on Enter.
3. On Mac: Open Outlook and hit on Preferences and reset all settings.
4. Click on Restart Outlook to check the issue is resolved.

Solution 2. Run Microsoft Support and Recovery Assistant

1. Download SARA from Microsoft and run the tool.
2. Select Outlook and follow on-screen instructions to fix errors.

Solution 3. Reinstall or Repair Outlook

1. On Windows: Control Panel and click on Program and features.
   
2. Hit on Microsoft 365 and tap on Change.
3. Press on Repair and follow instructions.
4. Mac: Drag Outlook to Trash and reinstall from Microsoft 365 Panel.
5. Sign in with your Account.

Solution 4. Analyze Crash Logs for Recurring Errors

1. On Windows click on Event Viewer and tap on Windows Logs.
2. Hit on Application and filter by Outlook.
3. Check errors.
4. On Mac: Click on Console and find Outlook.
5. Check Crash logs to find issues.

How to Prevent Outlook Crashes Issue?

1. Updated Outlook and Windows offer faster performance.
2. Regularly archived Outlook to maintain mailbox size
3. Only use trusted add-ins to prevent crashes.
4. Backup Outlook to protect you from file corruption or data loss issues.

Conclusion

If you have reached this point, then we hope you have the finest techniques to fix Outlook crashes issues. By following this guide, the chances of encountering Outlook crashes drop to nearly 1%. All methods have been tried and tested to keep Outlook stable and reliable. Stay tuned for our next post with more proven techniques.