See: http://kb.mozillazine.org/Deleting_autocomplete_entries http://kb.mozillazine.org/Password_Manager

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Thanks Cor-El. Had tried & completed both those with no success, but think I may have sussed the problem. The site requires different passwords on different pages, and I think it was remembering one from the "wrong" page, tho I'd clicked "this page only". Haven't been able to find a way round it tbh, sespite uninstalling/reinstalling firefox (remembered to click delete all personal stuff).

Now also have a problem loading gmail on firefox tho it worked at first ...not a 'supported browser'?

Unfortunately current Firefox versions will only remember the password for a domain and not separate passwords for a specific path. So if the user name is the same then Firefox saves the password that was last used with the name. I don't know if there are password or form fill extensions that can overcome this limitation.