I’ve lost my Administrator password for my Macbook Air. Looking in Help it says you can reset the password by inserting the setup media but I don’t seem to have that either. Am I stuck? Is it possible to get hold of replacement master media? And just to check, when the box pops up asking me to enter my username & password, is the username which is pre-populated in the box (which is my full name in upper case) definitely the correct name, or could it be that it’s it that’s wrong rather than the password?