dotnet general: Could someone provide some help or tips on creating “Registration Key” for client application?

I am designing an application in VB.Net which will be distributed to our clients. I want my clients to provide “Registration Key” when they first install the application. Further, I want this “Registration Key” to be unique for each installation, which means clients have to call us for the “Registration Key”.

I want to implement this scenario in order to prevent clients from distributing the applications to their friends, relative etc.

Job,

Although this is as well a good newsgroup for your questions, are there in
my opinion better newsgroups for your question

microsoft.public.dotnet.languages.vb
and the otherone I answered as well in
microsoft.public.dotnet.framework.adonet.

You can send as well one message to more dotnet Newgroups that is no
problem(crospost), however most do not like more messages (multipost) to
those newsgroups.

This was written about this question of you in the first one.
http://tinyurl.com/4gpq9

I hope this helps?

Cor