Thunderbird briefly flashes on the screen and then disappears

Thunderbird just quickly flashes on the screen and then disappears. This happened after I tried to set up a new account within Thunderbird. I was not getting it set up like I wanted so I closed it down. When I came back and started up Thunderbird it just quickly flashed on the screen and disappeared. I tried uninstalling Thunderbird. When I went to reinstall it complained it could not open MozMapi32.dll. I found this file in the Thunderbird folder and I renamed it MozMapi32.bak. Then Thunderbird installed. However, when I went to open it, it just quickly flashed on the screen and disappeared. I have a Dell Optiplex PC with Windows XP SP3. Does anyone have any ideas how I can get Thunderbird to start working again and be able to get my emails back. Please email me at j.keenan@yahoo.com as I cannot access my POP email. Thanks