Exceptions for a Sub-domain

We have DA  11.1 running on our main domain (DomainX.com).  It also kicks off in a sub-domain (sub.DomainX.com).  We do not have it installed on the DC's in the subdomain.  I tried to put in a specific computer exception as BE????.sub.DomainX.com (all workstations named BExxxx); also tried *.sub.DomainX.com; also tried BE*.sub.DomainX.com.  DA continues to try to run when I login to a workstation in sub.DomainX.com.

How can I prevent it from running?