Email Composing broken

I have a user who's using Mozilla 1.6 on a brand, spanking new G5 with 
10.3.3.

She was moving files around (I'm still a little vague on this point) and now
whenever she attempts to compose mail, Mozilla hangs. (She can read 
mail, but
she can't reply or start a new message to send.) What's more, when she tries
anything with composition in Preferences, the same problem occurs.

I've tried removing virtually every vestige of Mozilla I can find, then
restarting it to rebuild everything, but that doesn't seem to work.

Possible clue: My user was futzing with her old Eudora mail and trying to
read it with Word, which she said crashed many times.

Any ideas  -- even just how to do a clean install -- would be appreciated.

Greg
[email protected]