Duoserve licensing is based on the number of computers that are connecting to your account. At certain times, you may want to change which computers connect concurrently.
To do so, on any client computer go to:
Licenses tab -> Enter License Key... -> click on the second tab labeled Registered Client Machines
If you know which computer(s) you wish to remove to be replaced by another computer, click on its name and click Unregister Machine.
If you are unsure of which computer name(s) you wish to remove, you can simply unregister all computers and the next time each computer logs on to use the software, it will automatically be added to the License Manager.