No fumbling around with cracks/keygens, this is the easiest Nod32 you will ever install. Before anything else be sure to uninstall any current Anti Virus including any versions of Nod32 you may already be using, reboot your machine then follow the instructions below :
1 - Unrar
2 - Install - when asked check set update parameters later
3 - DO NOT REBOOT
4 - Goto the Update Menu
5 - Click on Update several times until it updates
6 - kOOl ! Yes thats also what I said =)
You now have a fully functional business edition with a trial period extended to aprox 24000 days = 65 Years.
I take no credit for this creation, just passing it along. This was created by a chap called Ranjan206 and as they say, sharing is caring so enjoy.