upgraded to window 10 lost all my contact info and prevous emal in my in box
upgraded to windows 10 when I load Thunderbird I have lost all the emails in my inbox as well several folder storing emails. I also lost all my contact list.
Alla svar (1)
Did you choose one of the options for Windows 10 preserving your data (e.g., reset, refresh, or possibly similar terms)?
Check for a folder named
C:\Windows.old\Users\your_username\AppData\Roaming\Thunderbird
If you do not immediately see AppData, make sure Windows shows hidden files and folders. To change that setting, see this article (hopefully it's similar in Windows 10): http://windows.microsoft.com/en-us/windows/show-hidden-files
Do you have such a folder?