MMC has detected an error in a snap-in

I recently installed Norton update 2009 (freebie till renewal) on 4/1/09.  When I went to defragment with Diskeeper Lite, I got the message:

 

MMC has detected an error in a snap-in.  It is recommended that you shut down and restart MMC.  (it also gave the option of running with the error), which I did.

 

I had also installed ServicePack 3 on 3/9.

 

I am running Windows XP PRO.  Any suggestions?