This is caused by a bug in the Q824145 patch. Click just under the slider in
the scrollbar, drag the slider, use the Page Up/Page Down keys or the arrow
keys.
You can uninstall the update and wait for the next one, but you'll be
re-opening a security vulnerability. http://www.microsoft.com/technet/security/bulletin/MS03-048.asp
You're right. The January update didn't fix this. Maybe next time :-o