Heres a few things to try Liz:
Are you using the latest version of Firefox?? (version 1.5) if not upgrade
Right-click on firefox icon on quick start, then click properties and add -p after "..../firefox.exe" .
Try running Firefox in Safemode (Start/All programs/Mozilla/Firefox(safe mode) if you still encounter the same problem then it`s possibly an extension that you`ve installed. If so ,uninstall the extentions (tools/extensions).
Unfortunatley there is no "repair" option in Firefox as there is in IE but if worst comes to worst you could uninstall Firefox and then reinstall it.
Hope this is some help.
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