First you need to open a terminal...
In Linpus Lite... you can do this by hitting Alt+F2 and then typing terminal and clicking the Run button.
When the terminal opens, type:
mv ~/.mozilla ~/.mozilla.old
and hit enter.
Now restart Firefox and a new ~/.mozilla directory will be created, and Firefox should start normally.
This worked for me.
Also try typing firefox in terminal this has also worked for me when other didn't.
sam, February 2011