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tkerby's avatar
tkerby
Copper Contributor
Jan 17, 2022

Duplicate emails on two domains (.com and .co.uk)

Hi

 

I'm in the process of migrating email from another service and I have three domains including a .com and a .co.uk. I'd like all emails to Email address removed to go to Email address removed

 

I know I could manually add aliases for each mailbox to include the .co.uk domains but that's a lot of work when my last provider let me use one domain as a mirror of another.

 

Any idea how to best do this in O365?

 

Thanks

Admin
exchange
Migration
office 365
  • surajbudhani's avatar
    surajbudhani
    Icon for Microsoft rankMicrosoft
    Jan 17, 2022
    You can either use email address policy to add secondary email address to all the users.
    Or you can just run one PowerShell command to update the secondary email address.

    $AllMailbox = Get-Mailbox -ResultSize Unlimited
    Foreach($A in $AllMailbox){
    $NewEmail = $A.Alias + "@domain.co.uk"
    Set-Mailbox $A.Alias -EmailAddresses @{Add=$NewEmail}}

    If the alias is john and email address is "john @ domain.com". This will add an additional SMTP as "john @ domain2.co.uk"