BTW - just tried to install Nmap on a Vista laptop and it failed - NPPtools.dll
missing -
It appears that this network monitoring API is not available in Vista ?

> C:\Nmap> nmap -T3 -sP 192.168.1.0/24
> Starting Nmap 4.20 ( http://insecure.org ) at 2007-09-01 09:28