We are a large enterprise and installing OCS 2007 in our lab environment. installing a Standard Edition Server, Communicator Web Access Server and Archiving server. Strictly for internal use only, will not be doing any external federation or Public IM with this test platform. I have already successfully installed the Standard Edition server and ready to get into the next steps of configuration and certificate installation. Question has to do with setup of SRV records to allow automatic client authentication. See the attached document which has an excerpt in it from the OCS Standard Edition Deployment guide. Our test lab Forest has a root domain we will call for discussion Labt and two child domains called Wizt and SWizt. These would be the actual domain names. DNS A record pointing to the FQDN of the Standard edition server has already been created. In DNS on one of our DC's I went to the Forwarding Zones and under the zone for Labt, Wizt and Swizt I created an SRV record associated with those domain names for sipinternatls which points to the name FQDN of the Standard Edition server. We also have mulitple email domain names for our users. So various users could have different SIP addresses associated with their the primary SMTP address of their mailbox. It states in the documentation that also for Automatic Client sign-in you will need to create an SRV record for each SIP domain. So I am wondering now if I need to do this and if so where will these SRV records be created ? I need someone to shed more light on this area for the Standard Edition Server.