How to write a expiry counter code in VB

I have a VB program which wants to add an expiry counter code in it. This expiry counter is to count the date which the program is installed for the customer, if the program has used for 30 days, a message will pop up saying that the program is already expired.
I don't know how to write the code for this date counter. Please help ASAP. Thanks!

You can download a free ActiveX control called ActiveLock that does all this (and more) from http://www.activelock.com

Chris Eastwood

CodeGuru - the website for developers
http://codeguru.developer.com/vb