how can i send people different places
 

i want people who access www.mydomain.com/members and it have popup and if person put a specfic l/p it will lead to members area and if person put wrong l/p and it will lead to other pages i setup wtih.. and i dont want it be setup to have it popup 3 times then it will be lead to error page u know what i mean?
hope u can help me out..

thanks