I have Vista and am trying to check my start up programs but Windows Defender won't open. It can't be reinstalled because it tells me I already have it, but it also doesn't appear in the uninstall programs list. I have AVG and AdAware too but evidently still need Defender for Software Explorer, at least. Any suggestions? Thanks in advance.

Why are you using Windows Defender to check your start up programs?

How to Disable (Remove and Uninstall) Windows Defender in Vista My Digital Life (http://www.mydigitallife.info/2008/02/22/how-to-disable-remove-and-uninstall-windows-defender-in-vista/)

You can always try going into program files or program files (x86) and find its directory. There could be an uninstall exe file you can double click on. It could still fail if it can find the uninstall string in the registry I suppose.

What's the alternative?

What's the alternative?MSCONFIG or CCleaner.