Czuch: Well, i am going through the Thunderbird: FAQs now for you, but i do not think anyone has had this problem by the looks of it. Most just export the file to Desktop (or wherever) then upload it to an on-line storage site or save it do disk.
My only other suggestion is to write to Mozy and see what they say, after all they must know where it would of been up loaded to and stored under. My only concern is did they bother with the address book ?
MadMonkey: They have all the saved files stored neatly into seperate categories IE Pictures, documents etc.... there is a category for thunderbird email and contacts. There is also one for outlook express email and contacts (which I never used)
I thinnk contacting mozy support might be a good next step...
MadMonkey: maybe, I havent looked thoroughly, but I did glance at the file size for outlook contacts etc, and it seemed pretty small, but i guess if I never uised it at all, it would be almost empty, so maybe I shall take a closer look. The Mozy support sent me back a prety standardized reply about how to retrieve files, but nothing specific to my issue!