i'm using program called "userport" and it works fine. Make sure you have an admin priveledge because it's don't work if you don't have the priveledge.
The program's purpose is to open the user priveledge because window xp and windows 2000 already blocked all user to access port.
Sometimes i must give logic '1' to all the control and data bus to make it works, after give that logic you can use the port normaly. That's what i get when i'm using visual basic 6.0