Profiles
Working with profiles:
A standard Firefox trouble-shooting technique is to create a new profile and use it for a while to see if the problem persists. If the problem goes away, it's likely that the old profile has become corrupted in some way. If this turns out to be the case, you can then copy your bookmarks, cookies and saved passwords from the old profile to the new one and delete the old profile when you're satisfied that all is well with the new one.
You use Firefox's "Profile Manager" to create a new profile. Click 'Start -> Run', enter "firefox -profilemanager" (without the quotes), click 'Create Profile', give the new profile a name and start Firefox using the new profile.
If the new profile works properly, copy the files bookmarks.html, cookies.txt, cookperm.txt, hostperm.1, key3.db and signons.txt from the old profile to the new one (if not all of those files are present, don't worry about it - that isn't unusual). Profile Manager is also where you would delete the old profile if/when desired.
