We are changing our external domain name - currently all Outlook 2007 clients are configured to connect to mail.companyname.com (internal redirect via A Record to 10.20.5.4 in Windows DNS) A new UCC SAN certificate is in place for all old/new/local names and working correctly for mail, autodiscover, and local. The new accepted domain is set up as well and receiving e-mails correctly. I am curious if changing the client settings on our CAS server will push to Outlook clients, or will I have to configure each client individually with the new mail.newcompanyname.com servername?

Thanks for the info - We are set to go live with the new domain next month, but I wanted to be prepared for any possible issues.