Open the "Licensing" program from "Administrative Tools". On the "License" menu choose New License. Enter 30 licenses (or however many you require to get the number to 30 if you've already entered some).
It doesn't matter where you got them, so long as you have enough CALs for each seat.
To delete licenses that are already entered select the "Products View" tab. Then highlight the licenses you want to delete and choose delete from the "Licensing" menu. You don't have to delete all of them, a dialog box will pop up and let you choose a number to delete.
You must also make certain that all the servers in your domain are set to Per Seat. To do this you can go to the individual server and open Control Panel-Licensing. Or you can do itfrom the Licensing program on any server and select the "Server Browser" tab. You can right-click the servers and choose properties to set them to "Per Seat".
You will also note eventually that users logging on from the same machine will all count against your total. You will need to set up License Groups (Options menu-Advanced-New License Group) to combine the users from a single machine and the system accounts into a single license. Otherwise the program will show you an alert, despite having enough licenses.
