Problem:
Which port should I use, 80 or 3306 ?Solution:
You should ALWAYS use port 3306, port 80 is for web access ONLY.The only exeception is when your Server Admin tells you otherwise, but it'll never be port 80, We can assure you.
This is a common error because unexperienced users first have access to a web and get a bit mixed up with wich port/server name to use.