Remove the Windows Defender. There are many utilities that do not cause problems.
How would I do that? I have tried
In a message dated 7/2/2009 2:07:17 P.M. Eastern Daylight Time,
Remove the Windows Defender. There are many utilities that do not cause
Like all applications, it should be removable via the Control Panels.
Windows Defender cannot be removed from Vista, but Windows Installer Cleanup Utility may be able to remove it.
You can also temporarily Exit Windows Defender from the ▽ symbol on the toolbar.
If I had to guess, I'd say that Defender is fighting over control with some other security-minded software you have installed on your system, not Adobe Reader. The forum post below should help you disable Defender in Vista: http://social.technet.microsoft.com/Forums/en-US/itprovistasecurity/thread/8ca5b361-6f54-4 9e7-bc9e-89d27765465a. It doesn't appear that the MSI cleaner will remove it though you can certainly try. Disabling it appears to be as good as it gets in Vista since Defender was integrated into the operating system much like IE.
Hope this helps!