The setup for the network installation by software distribution is a little different from the client setup.
Start the installation via Start - Execute msiexec /a "ixi-UMS Business Client Tools.msi".
You now have the option to state a directory where the prepared installation shall be deposited. This has to be a shared folder in the network.
After that you have to choose, which software components shall be installed on the clients.
See also "Available Features"
After that, Language, Messaging Platform, Adressing, Spool Folder and Allowed File Extensions are polled. Then the copy process starts.