[Vince]

Код:

An error has occured. (Error ID: 1064, You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''users' WHERE 'username' = 'mayne'' at line 1)

Reading is a profession in itself. You ONLY use the quotes (') for strings. Table and field names need only be wrapped in backticks (`) if they're SQL keywords.