In my scenario we have four branch offices and head office with different domains and different email address as below
User1@ Branchoffice1.com> using Exchange 2010
User2@ Branchoffice2.com > using Exchange 2010
User3@ Branchoffice3.com >using Exchange 2013
User4@ Branchoffice4.com> using Exchange 2010
User5@Headoffice.com> using Exchange 2010
According to management decision, I need to work to consolidate email address for branch office, meaning that all branch office users will get headoffice.com email address so that they can use both internal and external email address as headoffice.com instead of branchoffice.com.
At present, management do not want to move mailbox from branch office to head office rather only email flow so that all branch office users will send and receive email via headoffice.com sitting in their own email infrastructure.
Branch office users will be using branch office exhange sever for their active directory and exchange authentication but their email address will be headoffice.com instead of branch office.com. and we are not planning to move branch office users mailbox to head office. Could you please advise.
Note: I have asked kind of similar question as the URL below whereby Peter and Simon gave feedback but now requirement is slight change for that repost it again.