[Hall of Famer]

umm it does seem that for some users their admin account will not be created properly, the password is inserted incorrectly into database. I have no idea why this happens, and it's only for a few people. Sometimes it fixes their problem by reinstalling the script, sometimes it does not. Perhaps the admin account creation does not take care of special characters.

Anyway try resetting your password and see if that works(you will receive an email addressing how to complete this procedure, assuming your admin email is real). If it still wont work for you, you will have to create a new account and then go to phpmyadmin to make it admin. I will show you how to do that when you get there.