Seems I had inadvertantly messed with my Add-On management. The WuWebControlClass was disabled. I enabled it this way: In Tools,Manage Add-Ons... make sure your WuWebControlClass entry is listed under the Enabled section. If it's under Disabled, find the radio button for Enable, and enable it!. Fixed me up quick! Now, however, after loading SP2, it wants to have me install SP1 as a critical update. Oh well, can't win 'em all!