tdslori:
I tried this and it does not work.Yes it does. I've used it myself and retested it before I posted it. There may be other factors in your environment or the way in which you've tried this that have caused this not to work for you, but for the majority of people with the problem described in this thread, this will work.
Unfortunately you haven't actually provided any explanation as to what "does not work" looks like for you, or what you have done. So it's rather difficult to diagnose your problem or speculate on whether this might be a problem with your web host.
I did note two things however, you referred to not having used the password "Admin", but the password that I offered in my post is generated from "admin". Passwords are case sensitive.
Also you said that the resend password wasn't working. This could be due to using a user name that wasn't recognised (if it failed immediately) or your web hosts mailserver being down or refusing to send the email (if not working means the email didn't arrive).
Furthermore, if you do a resend password, your password will have been changed to that coming in the email, so another possible error would be to update your password via phpMyAdmin, then do a resend email, then try to log in - this will never work.
Finally, as the admin login function works fine for literally thousands of Zen Cart users, this could, as you suggest, be a problem in the environment in which your Zen Cart is hosted.