Can I restrict my ADusers, by their assigned Distribution groups on Outlook Clients rather than allowing them to choose any/all groups they want to send their e mail to?I am not worried about their selecting individual users (which do exist for them to choose), but the only group that they select within their Address Book should the only one they belong to. I am aware of the properties tab of the DG, that only allows me to restrict 'viewing' of the messages for the users within that DG. The constraint here is that user's might send to all DG's but only those not restricting his/her DG specifically, will be able to view the message. I want to restrict the users from 'sending' to other DG's alltogether. Something to restrict at the level where the messagesoriginate.The subtle cons of choosing the option to 'recieve only' from certain groups is: 1. The user gets a bounce back "Mail undeliverable" etc, if he/she gets to choose other DG's and Fire up his/her emails to a DG which is set to decline messages from him. 2. Persumably, if a Person B belonging to DG B sends a mail to Person A belonging to DG A. DG A is marked to recieve emails only from it's own DG A, now this is going to be a one to one correspondence between the two as Person B has not chosen the whole DG A in it's To: address field, would the mail from Person B reach Person A or would it be blocked?