I left the Desktop for a while and when I came back, Thunderbird, which had been sitting in the systray (Firetray) had disappeared.

Each time I restarted Thunderbird the programme launched, sat a few seconds then disappeared.

I ran "Thunderbird" in terminal and the result was "Segmentation fault". I looked in the logs and then I started searching the Ubuntu forums (my OS), Mozilla, Google and found a few comments about segfault but nothing to help me. I posted for help on the Ubuntu Forums and didn't receive any response at all so I don't really know where to get advice now.

I had not run any updates or changed anything on my (up until then) nicely behaving Ubuntu 10.10.

Anyone have any ideas please - any more information I should try to get from my system?

12 January no helpful responses. No further information. Moved to using Evolution and given up.

Try dropping the file system caches to force the system to reread the binary from disk, because a cosmic ray could have flipped a bit: as root, sync && echo 3 > /proc/sys/vm/drop_caches

Try updating Thunderbird if there's any new version available from the Ubuntu repositories.

Try running memtest86+ because it could be bad RAM.

Try rebooting.