Outlook Junk Mail Filter Stopped Working

I am putting this here because I feel I will get more response than in Email and Web Forum.

I have an a client whose Outlook Junk Mail Filter stopped working. A year ago when this happened we called a tech he knew in Fla who gave us a simple solution like open a folder and delete something and it then worked perfectly. Unfortunately we can't find him and neither of us remember what we did.

I have downloaded and installed all Outlook 2003 updates and junk mail filters. I installed the Outlook Spy bar so we can see the Junk mail Filter in the Inbox and delete it and let it be replaced but it isn't there to delete.

We have uninstalled and reinstalled Outlook and no change.
Recently when Avg Internet Security became corrupted, he had to reinstall the program and in doing so he installed the whole thing which includes a spam filter. I have read that Outlook suggests no other spam filter should be used so I uninstalled Avg and then reinstalled without the spam filter and still no chnage.
Anyone know the one step move that will reactivate the junk mail filter or any other ideas.

 

Thank you so much, but I didn't remember posting the answer on my own forum last year...one of my members did so we will try this first and if that doesn't work next time, yours is the next step.
http://www.kickenhardware.net/forum/showpost.php?p=67121&postcount=8

 

Well I thought that would work again but no such luck. Use of the "Outlook Spy" showed the junk mail rule isn't even there in the Inbox. This all started after SP3 install incidentally.
Immediately after.

 

I can't create a new pst file, this is a business and there is about 10 gb email storage.
My next step is to do all Windows updates including software updates which I am sure were not done. Then remove SP3 and if no change then do a new profile.