Have a look at John's Sticky note;
Post #2 has guidance how best to do this. If you want to save your bookmarks first, find the bookmark.html file in the Firefox profile folders and copy it somewhere else.
I hope that helps.
Windows xp home sp3
Firefox 3.51 won't open even in safe mode. I get the message
The instruction at Ox5a9288f8 referenced memory at Ox5a9288f8 . The memory could not be "written". Now I can't get any of my earlier version to open either. I get the same message for all of them. (Opera is working fine.) What should I do?