Can not limit access to Remote Desktop Group

[Compuz]

Have TSPlus installed on Win 7 machine, I7, with 32 Gb RAM, all windows patches applied, TSPlus 11 patch applied. System is on a domain 2008SBS and users come from the domain, not local.

TSplus connectivity is working, users can connect and work. This issue comes when under Security, Advanced Security Options, Limit Access to the members of Remote Desktop Users. If I check this box, I get the message requested secession access is denied. If I uncheck the Limit Access to the members of Remote Desktop Users box, the same user can log in and word. For clear reasons, I want this box on so not everyone can login.

I have checked:
User is a member of Remote Desktop Users group
User is not an administrator
all users seem to have the same issue

[admin]

Hello,

If you enable this security feature, you will need to open the user management interface to add manually the users that can remotely connect to your TSplus server to the remote desktop group.