CCleaner now in Win 10 deletes my password for AT&T sign in? in CCleaner Posted July 24, 2016 Have you checked that Firefox is set to remember passwords? The setting is in Options > Security On that page you can also view your saved logins to check that it is actually being saved. If it is shown as saved, close FFx reopen it and see if it's still there. If not then FFx is removing it on closing when it deletes cookies.