windows defender

when i try to open windows defender a window pops up saying "application failed to initialize 0x80070006. the handle is invalid" how do i fix it, and could that cause a lot of problems with my computer?

 

Here is some thing from Microsoft
http://support.microsoft.com/?kbid=935511

Did you just try too install vista or uninstall the windows defender.

 

neither, i kept getting a pop up when i got on the web saying my computer was infected but it wasn't from my antivirus program so i figured it was the virus doing that so i changed my antivirus program n it found 2 high threats so i took care of them. i thought i should go through and check the settings for the firewall and that message came up