The licensing tab under Administration maintains the license or licenses associated with your Evolution PBX system(s).
A single License:
An Evolution system with multiple licensed nodes:
If you need to change a license on the system click on the pencil icon to the right of the license number to edit it.
When the 'Change License' window appears, clear out the present license and input the appropriate license into the blank field:
After entering the new license, click on 'submit'.