Thunderbird installed ver 45. This seems to have wiped out a lot of functionality from the previous version. 3 of my email accounts no longer retrieve emails, and I can't get them to work. tried resetting one up, and that failed. the PRINT function only works occasionally. If I reply to an email, thunderbird will not let me print my reply. some of my message filters also no longer work. How can I reinstall an earlier version without further screwing things up. This version has become a veritable nightmare!