Outlook emails disappearing. What did you do to solve this?

I've had 2 experienced computer 'tekkies' work on my computer trying to solve this problem, with no luck. I've completed the steps re the Microsoft sites below. They are still disappearing! Some addresses are on my 'safe list' but this does not stop them from disappearing along with those not on the 'safe list'! In fact I deleted all my 'safe list' thinking it may be the cause of the problem. Did not make a difference! I know there this is a problem on OAL and maybe other servers as well. I did not re'set any 'filters' prior to this problem. Its been going on for a few weeks and I'm at my wits end to find a solution.

http://support.microsoft.com/kb/287577
http://support.microsoft.com/kb/253503/

Help! Please! Thank you in advance.