VS 2010 [RESOLVED] How can I implement an online authentication?

Hello everyone,

I have this new question, and I'm hoping you guys can help me :o

I'm developing a software, but I need to be able to lock it if user owes to the main company. (kind of... hmm... like netflix. If I don't pay netflix, they block my username, and prevent me from access to their content)

This doesn't need to be automatic, user will be blocked when I decide to. So I was thinking on a simple database with user and password fields, and change user's password when I want to block him. But my problem is that I have no idea on how to have that database online so that the software can authenticate whenever he needs to.

How can I do that? Any suggestions will be appreciated!

Thank you in advance!!