Recently a few machines on our network have started to act strangely when using Outlook 2003. Basically, the response to certain actions becomes very slow. For example, if you create a new email on the PC, when you click 'Send' the screen freezes for around 30 seconds before the compose window disappears and control is regained again. The same happens when you click on one of the menus in the compose window. Once you have clicked on a menu and waited 30 seconds, everything is normal speed - clicking 'Send' will be instantaneous. But then once you create another email the slowness returns.
We are running Windows Small Business Server 2003 SP1 with Exchange 2003 SP2. The clients are using Windows XP Pro with Outlook 2003.
I fixed one of the PCs by formatting the hard disk and doing a complete reinstall, but this seems a bit excessive. Any ideas how to fix this?