Why do ISA clients have trouble connecting to my server using the MMS protocol?
The default port that the MMS protocol uses is 1755. Some Internet Security and Acceleration (ISA) Server clients may have trouble connecting to this port because ISA uses different connection criteria for ports above 1023.You can correct this problem by configuring the WMS MMS Server Control Protocol plug-in to change the port to which the MMS protocol binds. Alternatively, you can create a file called Wspcfg.ini and save it to the folder named %systemroot%\Windows\System32\Windows Media\Server.