Removing “.onmicrosoft” extension from username

By now most of the Microsoft Dynamics CRM Online organizations should have been transitioned over from CTP platform to the new Office 365 billing system.  When this transition occurred, existing Microsoft Dynamics CRM Online users logins were appended with “” extension after their original login credentials.  For example, if your Microsoft Dynamics CRM Online username was then after transition to Office 365, it would be represented as

I noticed that some customers do not realize that they can remove “.onmicrosoft” in their username.  In order to remove the “.onmicrosoft” extension, here what you need to do.

  1. Sign into Office 365 Admin Portal with an administrator account, go to “domains” and add the domain you own to the list.  Follow the instruction that follows.
  2. After that you will need to follow up with your DNS hosting provider and provide them with TXT or MX record information and ask them to create either a TXT or an MX record in your domain.  It may take some time for the record information to be propagated.  If you have access to the DNS settings, you can do it yourself.
  3. After TXT or MX record is created, sign back into your Office 365 Admin Portal and confirm ownership of your domain name is now available in Office 365.
  4. Then go to “users and groups” and update each username extensions with the correct domain name.
  5. After that, notify all of the users of the changes in their username and have them sign in using the new username.  Normally this would be the same username that they used before, if it was their email address.

Note that user passwords are not impacted by this change; however, if users are using CRM Outlook client, they will need to sign-in again using the updated username as old username (with is no longer valid.  Hope this is helps.

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