You keep opening Mozilla Thunderbird in Windows, and it keeps finding the old settings. You want a fresh installation. What should you do?
Overview: Totally remove Thunderbird and reinstall it.
- Close Thunderbird
- Install CCleaner. It can be downloaded from here: https://www.ccleaner.com/ccleaner/download. (The free version will work.)
- Open it.
- Go to Tools -> Uninstall.
- Find Mozilla Thunderbird and highlight it.
- Click Uninstall.
- After it uninstalls, click "Custom Clean".
- Make sure nothing is checked in the Windows tab.
- Click on the "Applications" tab.
- Click on every option under Thunderbird.
- Click "Run ccleaner"
- Go to C:\Users\jdoe\AppData\Roaming\Thunderbird (where jdoe is the username that has the old Thunderbird settings). Delete this folder.
- Go to C:\Users\jdoe\AppData\Local\Thunderbird (where jdoe is the username that has the old Thunderbird settings). Delete this folder.
- Reboot your computer.
- Reinstall Thunderbird and configure it again.