I don't think it's possible to remove Child-Domains if the parent is still added. I have removed all of my Tree-Domains from the list of domains that have been shown in the VMware Horizon View login pages, by running the VDMADMIN command, but if any domain is still included, all of its Sub-Domains will be listed.Please mark my comment as the Correct Answer if this solution resolved your problem
Well ... Everytime i tried to exclude a domain i have used the FQDN. Now i've tried the NETBIOS and it works ...also with subdomains.
Thanks for your answer