Have a look here:
http://www.microsoft.com/windows/products/winfamily/defender/default.mspx
I got Windows Defender with my computer. Today I went to the Software Explorer section and looked at the Start Up list. When I click on an entry, the "Remove, Disable, and Enable" buttons aren't highlighted. I went to the Windows site and tried to download it again (the version given was different from the version I have) but it said I got it with my computer. Apparently, because I didn't buy it outright,I can't update it. Does anyone know how to get the buttons to highlight so I can disable a program from starting up when Windows starts up.
I did just go to msconf and unchecked some there, but I wonder why Windows Defender doesn't work right.

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