I had to install Groove 2007 today in order to participate in a project I'm doing and after installing it I found that my Outlook 2003 Junk Email Filter no longer worked. I thought I would have to reinstall Outlook or worse, restore an image of the operating system.
I didn't want to do either one, so I uninstalled the Outlook 2003 Email Filter Update in the Add/Remove Programs applet in Windows XP SP2. I made a note of what the KB number was for the filter version I removed and looked it up on the Microsoft Web site. I then manually downloaded the Outlook Junk Email Filter executable file and reinstalled the filter version I removed.
Bam! It worked. Junk email filtering is working again and I don't have to reinstall Outlook or restore the OS. Yay!