profiles.ini is a '''file''' not a folder, and it should be in your Firefox folder above the Firefox profile folder. You could have more than one profile. Firefox will often try to recreate a profile.ini file or a profile when it runs into problems. You could have a profile.ini that is hidden or you have not yet found it. If that file is wrong and points at a locked, inaccessible or none existent location you may have a problem that Firefox can not solve by itself. *See http://kb.mozillazine.org/Profiles.ini_file * http://kb.mozillazine.org/Profile_folder_-_Firefox Have another look for ''profiles.ini'' but when you find it rename it (maybe ''profiles.ini.faulty'') that should be enough for Firefox to recreate a profile.ini , a profile & be able to start again. * This may help if you are having problems with hidden files <br /> http://kb.mozillazine.org/Show_hidden_files_and_folders The file ''profile.ini'' is short and the content of the now renamed file ought to give you a clue as to what is happening.