Sony PCG-GRX590 laptop running WinXPpro and Outlook 2003 (it happened with Outlook 2002 as well). When I select mulitple messages, e.g. when deleting, the display flickers for quite a period of time which is dependent on the number of messages selected. A hundred messages will take over several minutes before it returns control and allows me to take the next step. This situation occurs probably 90% of the time. The only other thing I can point to is that this machine has a a jog dial hardware feature that came pre-installed. I've not been successful removing it. There's an icon in the system tray that will flicker in time with the outlook display.