Install Vista without serial?

I recently found that I needed to purchase a program that is only built for vista. I just found my installation disk but I can't find the serial key. I heard that it was possible to install the disk without the key. Can anybody confirm this?

Not that I have ever seen or heard and I do a lot of installs of XP and Vista for clients. You need the key. Also is your copy of Vista installed on another machine?

Actually you can install Vista without the key, in which case you
get a 30 day free trial. Just don't enter the key, and also tell it
NOT to automatically activate. It will tell you that not entering
a key will cause problems, but that simply means that after
the 30 day trial is over, Vista will stop working.

You can enter a key anytime during the 30 day trial. Microsoft
even sells them online if you determine the key is permanently
lost. Hey, a small piece of paper is easy to throw out accidentally.

Try googling: Vista 30 day trial

Lots of info out there.