Cutover Migration with multiple SMTP domains

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  • MarkJones

    Hi Guys.

    Firstly I will start by saying I’ve done a cutover migration with a single SMTP domain no problem, so I understand the steps required.

    I’m starting a cutover migration from SBS2008(fully patched) to Office 365, this migration is for 50 Mail enabled users and some distribution groups. On this Exchange 2007 Server I have 5 accepted domains…. lets call them,,, and (originally this server was only for

    I have an SSL cert for which contains and used for Outlook Anywhere.

    Over the years the other domains have been added, but they have no SSL CERT associated with them, I don’t have autodiscover DNS records for ,, or anywhere(these are only used by internal Outlook clients)

    The mail enabled user, some have primary email address for and additional address from the other 4 domains, while other mail enabled users will only have a single/primary address from .etc(so in effect not all users have the original as an address)

    So far I have setup my Office365 account as far as having the 5 domains verified by adding a TXT record in external DNS.


    When I continue with the migration I don’t understand how Office365 will be able to sync email messages from my,,, addresses which don’t have an SSL CERT or autodiscover(I can setup,…. etc if required).

    Do I need an address of on all the mail enabled accounts and distribution groups to get this to work…?
    If I setup, …etc.. pointing to the same external IP address as what points to, will this allow it to work…?
    Set the user principal name in SBS2008 active directory to this is set to [email protected] for all users)

    Hope you understand my explanation.


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