OutWit Hub For Firefox 2.1.1+: When updating from 1.0 to 2.0 then to 2.1 successively, it can happen in some cases that the previous extensions do not unistall properly. In such cases, restarting Firefox usually solves the problem. You can also manually uninstall all outwit extensions and reinstall them from outwit.com. This process will not delete your profile (scrapers, macros etc.) or your registration information.
Notes: If you wish to backup your profile folder anyway (which is never a bad idea). You can locate it by typing “about:support” in the address bar.
Do check in the add-on panel of Firefox (Tools>Add-ons) that the installed outwit extensions are the latest versions: See the version history for OutWit Hub, OutWit Images and OutWit Docs.