I'm setting an new exchange enviornment where mgmt does not want the users to be able to send email back & forth and only be able to see there ID in the GAL. Intially the goal is to use the Calendar & Contact functions in Exchange only.

Hi, Per user or group message restrictions, you can Open ADUC -> Right click the User/Group you want to set->choose Properties->Exchange General tab--->Message Restrictions. Under this options, you can set allow messages from everyone except from some user or group. Please add the user/group you want to block. Hope you want this. -Jason