Outlook performs slowly or stops responding when using RPC over HTTP
When you use Outlook 2003 to connect to the Exchange server by using a remote procedure call (RPC) over HTTP, Outlook 2003 may perform slowly or stop responding altogether.
Check the following:
- The Bypass proxy server for local addresses check box is not selected in the Internet Explorer options.
- Windows XP Service Pack 2 is installed.
If the above does not fix the problem, or you do not want to install Service Pack 2, you should install the following hotfix from Microsoft: