How to migrate company's e-mail address?

[6495]

Our company just recently changed ownership. Very soon we will change from georgew@123.com <mailto:georgew@123.com> to georgew@abc.com <mailto:georgew@abc.com>. We are running Exchange 5.5. I am very new to Exchange. Our e-mail address or MX record is hosted by another company. I don't know what else I should do other than just give them the new name. Someone suggested that I should run both names/addresses parallel. If I run parallel, where exactly should I add this new name? From Internet Mail Service Properties --> Routing tab and each individual recipient properties-->E-mail Address tab?

I would really appreciate if someone could send me some technical details and what the best way to migrate to a different e-mail address.

 

[Zelandakh]

Tell your ISP to send abc.com emails to the same place they send 123.com already.

Do not reroute your emails and for every user who currently exists add in their new abc.com email address.

In the templates add in the abc.com address too and so for every new user they will get both by default.

Now both of them work..

 

[6495]

Thank you very much for your kindly reply,Zelandakh!

Currently, under Exch Admin IMS-->Routing the settting is on &quot;Reroute incoming SMTP mail(requied for POP3/IMAP4 support&quot;. So, after abc.com is added here I need to select &quot;Do not reroute incoming SMTP mail&quot;...? And why...? As Exch Admin help topic states that &quot;if mail from POP3 or IMAP4 clients is to be routed to recipients outside the Microsoft Exchange Server organization, you must configure the Internet Mail Service to reroute mail.&quot;
I guess I don't quite understand exactly what &quot;POP3/IMAP4 support&quot; means here.

Would very much appreciate if I receive further feedback.