O365 users back sync RRS feed

  • Question

  • I have an old environment where AD exist and around 3000 users whose account already exist in O365. Now there is a merge up with a new company because of which new AD will be formed. 

    Challenge is, we need these same 3000 users whicha already exist in O365 to be created in new AD. All machines will be newly joined to domain( Xp + Win7 + win8). Users are same old domain users whose mailbox already exist in O365 with old domain name

    Is it possible by any means?

    Wednesday, May 11, 2016 11:48 AM

All replies

  • Is it possible... yes. But there are a number of questions that need to be answered and this will determine the path required. 

    1) Are the 3000 user moving to a new AD domain, with a new UPN?

    2) Do you plan to keep the same Office 365 tenant?

    3) Will the SMTP domain change?

    Wednesday, May 11, 2016 2:08 PM
  • 1) Are the 3000 user moving to a new AD domain, with a new UPN? Yes, with New UPN. They will be freshly created. Old domain data and access will not be required as it is new company and everything is new. Email is an exceptional to this. 

    2) Do you plan to keep the same Office 365 tenant? Tenant is same but domain is different. presently but needs to be changed to

    3) Will the SMTP domain change? Yes , it will change from to

    Wednesday, May 11, 2016 4:54 PM
  • Can you please share more details? Like

    How will you move users to another forest? Will you use any Migration Tool or new user creation?

    Do you want to keep old SMTP Address as well?

    Since you will be changing UPN and SMTP both, then this will change UPN and SMTP in Office 365 as well. Are you fine with this approach.

    Do you have Exchange installed locally (Version as well)? and in new forest as well? if not how you moved mailboxes to Office 365 in past?

    Saturday, May 21, 2016 5:06 PM
  • Hi,

    There is no user write back feature in O365, you can only sync back passwords from O365 to On-premises AD.

    Now if you want to create these users in your AD, you can export the required data in CSV and then create them in your AD using the same csv with AD powershell. This is only valid when their mailboxes not need to migrated. If you also need to migrate the mailbox, you may need to contact MS for tenant to tenant migration.

    Please mark as an answer if this answers your question .


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    Saturday, September 15, 2018 4:40 AM