Can't open Windows Defender

[blueeyes]

I'm using Vista and like the subject line says I can't open Windows Defender.
I can't find it in the add/remove programs either. I used to see the icon
until it disappeared. At one point I saw the icon in the lower right corner
again and it said something about a virus, I think. It's been so long I
apologize if I don't remember it right. I've tried everything search-wise
from my point of understanding. I'm not a computer wizz. Can anybody help me
out here? I'd really appreciate it. Thank you.

 

[Bill Sanderson]

Type Windows Defender into the search box that comes up when you hit the
round "start" button in the lower left of your Windows desktop.

What anti-virus program are you running? Many anti-virus programs disable
Windows defender. This is expected behavior.