This utility is available free from http://acm.archvision.com. For instructions, see the ArchVision Content Manager Help (http://acm.archvision.com/help).
Now you must specify the location of the ACM so that Revit can access the additional RPC content.
By default, Revit attempts to connect to the ACM using the IP address 127.0.0.1 (the local host) and port 14931. If it cannot connect to the ACM there, it attempts to start the ACM executable that you specify here.