Device Management > Manage Device Tree > Delete
You can only delete empty domains to which no mobile device belongs.
You cannot delete the following domain types:
the "Mobile Security" domain (the root domain)
the "default" domain (the domain that a device belongs if you did not specify a domain during device addition)
domains with associated devices
In the Device Management screen, select a domain from the domain tree. Make sure there are no mobile devices associated with this domain.
Click Manage Device Tree > Delete.
A warning screen displays. Click OK to delete; otherwise, click Cancel.
After you have deleted a domain, the domain name will not display in the Domain drop-down list in the Add Device or Edit Device screen.