I've recently installed Thunderbird 2.00.16 onto my fresh Ubuntu Hardy install and I'm now experiencing resets back to the login screen, seems to be random but it happens every session at least once.

Could it be Thunderbird and, if not, has anyone got any ideas?

Thanks in advance

Eric

Try opening a terminal window and running Thunderbird from there. You may see helpful messages before you get logged off. You can also capture messages in a text file by redirecting the Thunderbird error output as follows:

Thanks for the reply. The errors I get are:-

/home/eric/.themes/Clearlooks-Olive/gtk-2.0/gtkrc:43: Clearlooks configuration option "sunkenmenu" is not supported and will be ignored.
/home/eric/.themes/Clearlooks-Olive/gtk-2.0/gtkrc:44: Clearlooks configuration option "menuitemstyle" is not supported and will be ignored.
/home/eric/.themes/Clearlooks-Olive/gtk-2.0/gtkrc:45: Clearlooks configuration option "listviewitemstyle" is not supported and will be ignored.
/home/eric/.themes/Clearlooks-Olive/gtk-2.0/gtkrc:46: Clearlooks configuration option "progressbarstyle" is not supported and will be ignored.
*** Calendar schema version is: 7

Nothing seems to be critical though, could it be my theme?

I agree with you. Those errors don't appear to be the problem. I doubt it would be the theme because theme problems would probably result in Thunderbird using its default theme or, at worst, cause Thunderbird to crash. I doubt that a theme problem would cause your X session to restart.

I couldn't find anything at google.com. Most of the Thunderbird crashes listed there are for older versions of Thunderbird and were posted in 2007.

If you have add-ons then try removing them. Otherwise just keep up to date on patches or use another email client. Evolution and Kmail are both very good.