Viewing port used in IIS
To check the IIS port, open IIS, expand Web Sites, right-click on the site you're wondering about, choose Properties, under Web site, view TCP port

Viewing port used in agent-server communication
Default port for agent communication to the NS is port 80

You can change this at /altiris/ns">http://<servername>/altiris/ns, Configuration tab, Altiris Agent > Altiris Agent Configuration > All Desktop computers (excluding 'Package Servers'), then click the Advanced Settings tab on the far right.  Check the box for 'Specify an alternate URL for the Altiris Agent to use to access the NS,' then modify the Server Web: to include a port number after the name, e.g. http://server.yourdomain.com/Altiris/ becomes http://server.yourdomain.com:1234/Altiris/

You would have to modify this URL for each install task you wish to modify in addition to the Desktop (not Package Servers) install.

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