Instead for your group try the following:
valid user = [Domain Name]\[AD Group Name]
For the domain centrify.com and the group IT_Members the entry would be:
valid users = +CENTRIFY\IT_Members
Instead for your group try the following:
valid user = [Domain Name]\[AD Group Name]
For the domain centrify.com and the group IT_Members the entry would be:
valid users = +CENTRIFY\IT_Members