A component of the new Microsoft Windows XP SP2 Security Center that warns you when you run a .exe (executable) file that you have downloaded from the internet. Its purpose is to stop n00b users from getting infected with malicious software, but for us advanced users it's just a royal pain in the ass.
When I downloaded Mozilla Firefox 1.5 Beta 2, Windows XP's Security Warning prompt tried to stop me from installing it.
by Home slice October 26, 2005