Fix: Thunderbird not Responding on Windows

Mozilla Thunderbird is a free popular cross-platform email-client used by plenty of people. However, recent versions of Windows 10 don’t seem to run very well alongside it as plenty of its users have reported that the program simply freezes on certain commands and in certain parts.

Mozilla Thunderbird is not Responding

The problem has been resolved in numerous ways and we have decided to incorporate the most successful methods in this article in order to help people who are struggling with this problem. Make sure you follow the instructions below and carefully and you will hopefully resolve the problem.

What Causes the ‘Thunderbird not Responding’ Error?

There is a short list of possible causes for this problem. The list can be quite useful in order to correctly troubleshoot the problem and perform the right method. Check it out below:

  • Your antivirus may be interfering with Thunderbird and it may prevent it from connecting to the Internet properly.
  • There are several problematic settings which can be turned off in Mozilla Thunderbird. Consider doing so!
  • Some program or service may be interfering with Thunderbird and the only way to test this is via clean boot.
  • If you are using McAfee Internet Security, it doesn’t play alongside Thunderbird very well and you might want to replace either of these programs.

Solution 1: Add Thunderbird to Exceptions in Your Antivirus

If you are using a free antivirus, chances are that it may be blocking Mozilla Thunderbird from connecting to the Internet properly or from accessing certain files on your computer. Either way, the problem can be solved by adding the program’s executable to the exclusions list in your antivirus.

The process will differ from one antivirus to another but we have decided to list out the paths to this option in the most popular antivirus tools.

  1. Open the antivirus UI by double-clicking its icon at the system tray (right part of the taskbar at the bottom of the window) or by searching for it in the Start menu (Cortana).
  2. The Exceptions or Exclusions setting is located in different spots with respect to different antivirus tools. It can often be found simply without much trouble but here are some quick instructions on how to find it in the most popular antivirus tools:

Kaspersky Internet Security: Home >> Settings >> Additional >> Threats and Exclusions >> Exclusions >> Specify Trusted Applications >> Add.

AVG: Home >> Settings >> Components >> Web Shield >> Exceptions.

Avast: Home >> Settings >> General >> Exclusions.

Settings Exceptions in AVG
  1. You will need to add the executable file the box which will appear prompting you to navigate to the required file. The best way to locate it is by right-clicking its shortcut on the Desktop and choosing the Open file location option from the context menu. This is the address to navigate to. Sometimes you might have to add the path to the folder where the program is installed and sometimes to the executable.
  2. Check to see if you are now able to use the program without receiving the ‘Not responding’ message after running Thunderbird. If the error still appears, you might consider using a different antivirus or firewall tool, especially if the one giving you the problems is free!

Solution 2: Disabling Windows Search to search messages

There is a problematic feature Mozilla Thunderbird uses and users have reported that disabling this feature helped them resolve their problem. The cause may have something to do with the overall integration of Windows Search into the program which needs to be disabled.

  1. Launch Mozilla Thunderbird by double-clicking its icon on the Desktop or by searching for it in the Start menu and clicking the first option.
  2. Click the Tools button on the menu bar and choose Options.
    Opening Thunderbird options
  3. After the Options window opens, navigate to the Advanced Inside it, stay in the General sub tab and check under System Integration for the Allow Windows Search to search messages option. Uncheck the box next to it and click the OK button at the bottom in order to accept the changes.
    Enabling the “Allow Windows Search to search messages” option
  4. Check to see if Mozilla Thunderbird still displays the ‘not responding’ message.

Note: It might be useful to navigate to Advanced >> Network & Disc Space and uncheck the Automatic Compact option.

Solution 3: Use Clean Boot to Find the Cause

Clean booting in order to successfully detect a service or a process which starts up with your computer is definitely the number one solution. Some other services simply bother the media player because of permissions and you will need to deduce which one it is by simple elimination.

  1. Use the Windows + R key combination on your keyboard. In the Run dialog box type MSCONFIG and click OK.
  2. Click on the Boot tab and uncheck the Safe Boot option (if checked).
  1. Under the General tab in the same window, click to select the Selective startup option, and then click to clear the Load startup items check box to make sure it’s not checked.
  2. Under the Services tab, click to select the Hide all Microsoft services check box, and then click Disable all.
Disabling all non-Microsoft services
  1. On the Startup tab, click Open Task Manager. In the Task Manager window under the Startup tab, right click on each startup item which are enabled and select Disable.
Disabling startup items
  1. After this, you will need to perform some of the most boring processes and that is enabling the Startup items one by one and restarting your computer. After that, you need to check whether the problem appears again. You will need to repeat the same process even for the Services which you have disabled in Step 4.
  2. Once you locate the problematic startup item or service, you can undertake action in order to solve the problem. If it is a program, you can reinstall it or repair it. If it is a service, you can disable it, etc.

Solution 4: Uninstall McAfee Internet Security

There are some antivirus tools which can really mess up some of your programs and slow down your computer. McAfee antivirus tools are a great example of antivirus tools which can sometimes do more damage than good on your PC so consider finding a better alternative!

The problem can also be worked around by disabling antivirus shields and real-time protection while you are using Mozilla Thunderbird but that solution leaves your computer open to malware attacks and you can often forget to turn the shields back on.

  1. Click on the Start menu button and open Control Panel by searching for it. Alternatively, you can click on the gear-like icon in order to open the Settings tool if you are a Windows 10 user.
  2. In Control Panel, set the View as setting to Category at the top right corner and click on Uninstall a Program under the Programs section.
Uninstall a program in Control Panel
  1. If you are using the Settings app on Windows 10, clicking on Apps should immediately open a list of all installed programs and tools on your PC.
  2. Locate McAfee Internet Security in Control Panel or Settings and click on Uninstall or Remove.
  3. You should confirm any dialog boxes which may appear asking you to really uninstall McAfee Antivirus and follow the instructions which will appear in the uninstallation wizard.
Uninstalling McAfee Internet Security
  1. Click Finish when the uninstalled completes the process and restart your computer in order to apply the changes. Check to see if the problem persists!

Kevin Arrows

Kevin Arrows is a highly experienced and knowledgeable technology specialist with over a decade of industry experience. He holds a Microsoft Certified Technology Specialist (MCTS) certification and has a deep passion for staying up-to-date on the latest tech developments. Kevin has written extensively on a wide range of tech-related topics, showcasing his expertise and knowledge in areas such as software development, cybersecurity, and cloud computing. His contributions to the tech field have been widely recognized and respected by his peers, and he is highly regarded for his ability to explain complex technical concepts in a clear and concise manner.