Exchange Client Runs Slowly or Delays Opening with Proxy

ID: Q164089

The information in this article applies to:


Microsoft Exchange Client runs very slowly or delays opening for long periods of time when it is opened on a Winsock proxy client computer. On IPX networks where the proxy is connecting to the Internet with RAS, this behavior causes the proxy to auto-dial.


This problem occurs because of a known problem with the Microsoft Exchange Client for Windows 95. This client makes a Winsock call even if TCP/IP is not used on the client computer. This causes a DNS name lookup to be requested by the proxy server. Usually, the delay for this name lookup is increased because the proxy server must dial and log on to the Internet.


To prevent this problem from occurring, modify the global Mspclnt.ini file (in the Proxy server Clients directory) as follows. (NOTE: Remember to refresh the Winsock Proxy files on the client before testing; otherwise, the WSP clients will refresh themselves every 6 hours.)

Add the section:

(For Microsoft Exchange Client)

(For the Outlook client)

This will disable WSP for Microsoft Exchange Client, thus eliminating the delay, and the use of the proxy to access the local computer running Microsoft Exchange Server. You can also optionally add the following section for the MAPI spooler:


Keywords          : kb3rdparty pxsinterop 
Version           : 1.0 2.0
Platform          : winnt 
Issue type        : 

Last Reviewed: August 12, 1999