Recently a Vault 2013 customer had installed the upgrade from Vault Server 2012 and had chosen the option to select another port besides the default port 80 when configuring the Internet Information Services (IIS) during setup.
He had chosen Port 8080, which is a common alternate http port. However you can use any unused port between 1-65535
While it is possible to select a port other than the default HTTP port 80 for the IIS configuration for Vault Server 2013, there are cautions that Autodesk points out in the "Best Practices for Implementing Autodesk Vault" white paper that warn against running Vault on a server shared by other applications.
If the reason to change the default port is to accomodate another application, you may want to consider running Vault on a dedicated server.
IIS hosts components known as .NET Web Services. The web services provide all the logic needed for the vault to operate. Web services communicate with the other components via standard HTTP methods. In fact, all vault communication is via these Web Services over the web server’s port 80.
If you change the default port during the installation configuration, you will need to modify the login to connect the server.
To log in from the client side you will need to change the server name from “SERVERNAME” to “SERVERNAME:8080” at the login screen to add the selected port. Change "8080" to the port you selected if different. You will also use the name of your Vault server.
Additionally, you may also get a message "iis is not running as the default web server" when you attempt to install Service Pack 1 for the Vault Server. See the Related article at the link below to resolve this.