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Thunderbird is one of the most popular, widely used, and free-to-use email clients. It supports both POP3 and IMAP server configurations and allows users to use multiple email addresses simultaneously. Thunderbird stores emails, contacts, caleandars and other user information in MBOX files. It provides multiple advanced features to users, but sometimes users encounter Thunderbird crashing/freezing errors. But don’t worry, this article will provide the best solutions to address the Thunderbird crashing or running slowly issue.
Why is Thunderbird Crashing/Freezing Reasons
There are many reasons Thunderbird keeps crashing. Let’s discuss them:
- Thunderbird profile stores all emails and other user data; if the profile gets corrupt, Thunderbird crashes frequently.
- If you are using an outdated version of Mozilla Thunderbird.
- If the size of the mailbox exceeds the limit, and the mailbox is full.
- Installing add-ons that are not supported.
- If the Mail Summary File is corrupt or damaged.
- Antivirus may be causing conflict with the Thunderbird application causeing it to freeze.
- You are using outdated hardware that can’t handle the Thunderbird application.
After knowing the user’s concern and reasons about this topic, let’s discuss the simple method or tricks to resolve the issue of Thunderbird Crashing/Freezing on Windows 10. If users want to convert Thunderbird SBD to Outlook PST, then the alternative method will be best.
Top Solutions: Fix Thunderbird Crashing/Freezing on Windows
There are some proven methods given in the section below to stop Thunderbird from crashing or freezing. Properly execute every step to resolve non-responsive Mozilla Thunderbird difficulties:
1. Use Thunderbird in Safe Mode without Add-ons
Running Thunderbird in safe mode would disable all add-ins installed. This is the best way to identify if an add-on is the cause of slow Thunderbird.
- When you start Thunderbird, use the “Shift” button while launching Thunderbird.
- Click on “Continue in Safe Mode.”
- If Mozilla Thunderbird works fine, then “go to Tools > Add-ons.”
- After that, disable unnecessary extensions.
Note: This step is the easiest fix if your Thunderbird keeps crashing.
2. Update Thunderbird to the latest version
If users use the outdated Thunderbird version, then its compatibility creates issues with latest Windows systems.
- Open/Launch Thunderbird.
- Click Help and then get the “About Thunderbird.”
- If any updates are available, then it will start downloading automatically.
Attention: If you regularly check the updates of Mozilla Thunderbird, it can give better performance and fewer crashes without any delays.
3. Make a New Thunderbird Profile
Sometimes Thunderbird’s entire profile is corrupted and cannot be fixed. Creating a new profile is one solution that can fix Thunderbird freezing/crashing.
- Start the process by using “Win + R” and then typing this: “thunderbird.exe -p.”
- Click on “Create Profile” > then “Name it” > after that “Finish”.
- Use your fresh Thunderbird profile.
Users’ Note: Users can import emails later using the “ImportExportTools NG add-on” in MBOX format. If users’ Thunderbird ImportExportNG Tools not working, then try this fix.
4. Disable Hardware Acceleration
If you are disabling the hardware acceleration, then it can fix Thunderbird freezing during launch.
- Go to Tools > Options and then Settings.
- In “Under General”, scroll to the Performance.
- Uncheck “Use hardware acceleration when available.”
- After that, restart Thunderbird.
Attention: These steps will help users whose Thunderbird keeps crashing on Windows 10. This error will usually show in Windows 10 and is related to graphic errors.
5. Repair Folder Index(.msf) Files
If you have corrupt MSF (Mail Summary Files), it can make folders unreadable. MSF files make Thunderbird unresponsive.
- Right-click on the folder, such as Inbox, Sent, etc.
- Select Properties and after that, click on the “Repair Folder” button.
Spotlight: This method will be helpful if your Thunderbird crashes when trying to open any specific folder.
6. Add Thunderbird to the Firewall White List
Some of these security applications can interfere with Thunderbird’s processes during the synchronization process.
- Open the antivirus settings.
- Add Thunderbird as “thunderbird.exe” to the exceptions.
- Allowed apps list that does not stop Thunderbird from launching.
Please check: Users need to avoid real-time scanning of the Thunderbird profile folder if they don’t want Thunderbird crashing/freezing.
7. Reinstall Mozilla Thunderbird Cleanly
If all the above steps didn’t work, then try to install a fresh Thunderbird on the system.
- First, create a backup of your profile from:
“C:\Users\
\AppData\Roaming\Thunderbird.“ - Delete Thunderbird properly.
- After that, go to the official Thunderbird website and download the latest version of Thunderbird.
- After downloading the new Thunderbird, restore the backed-up profile from your computer’s Backup folder.
A Safe Note: A clean installation often fixes long-term Thunderbird crashing problems.
8. Disable Windows Compatibility Mode
Users unknowingly run Thunderbird in compatibility mode, which creates crashes on Windows 10.
- Right-click on the Thunderbird shortcut.
- After that, choose Properties > and then click on the “Compatibility tab.”
- Uncheck “Run this program in compatibility mode.”
- After these steps, restart Thunderbird on pc.
Check this point: If compatibility mode is no longer needed for Thunderbird, then it can be fully compatible with Windows 10.
9. Reset Thunderbird Toolbars & Layout
If Thunderbird freezes while opening or syncing mail, then its layout file might be corrupted.
- Close Thunderbird properly.
- Go to the profile folder:
“C:\Users\
\AppData\Roaming\Thunderbird\Profiles\ .default\“ - Delete these files: xulstore.json | session.json
- Restart Thunderbird.
- The UI will be reset to the default.
An Alternative: If you use all 10 manual methods to resolve the Thunderbird crashing/freezing, then you need an advanced approach that is suggested by most expert professionals. Users can use the best solution to overcome Thunderbird freezes and extremely slow-running issues. Use BLR MBOX converter software that helps you convert Thunderbird emails on Windows OS. This MBOX to PST application will save you from data loss and file corruption issues. If users don’t want to try the risky free method, then try the professional application.
Final Thoughts
If your Thunderbird email client is not responding or freezing frequently, then there is no need to panic. With some basic knowledge, you would be able to get the Thunderbird to work again effortlessly. This blog gives you complete information on how to deal with Thunderbird crashing/freezing errors that users encounter. But if Thunderbird keeps crashing even after all these fixes, then users need to consider contacting Thunderbird support.
