im just starting to learn php. im working on a basic login/user registration form and it works fine on localhost, but after i uploaded it to my server i get this error messag when i input correct login info:

Warning: mysql_num_rows( ): supplied argument is not a valid MySQL result resource in D:\Hosting\8927 368\html\EKMN\l ogin.php on line 53
The username you entered was not found.

here is my code:

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