Forum Discussion

StefanKi's avatar
StefanKi
Iron Contributor
Jul 28, 2020

Exchange Migration PST Export

Hello, I have a very bad exchange. The Exchange server barely works. The contents of the mailboxes should be migrated to Office 365. Because I can't configure anything on the Exchange Server I want...
2013
exchange online
office 365
HidMov's avatar
HidMov
Steel Contributor
Jul 28, 2020

Hi StefanKi

 

I'd try and see if you can set up a cutover migration if possible, but if the Exchange really is in a bad way and a PST export/import is the only thing it'll respond to, then I'd look at the following.

 

At point 3, you want to change the MX records to point to your Exchange Online so new email flows there - also change your autodiscover A Record. You will probably need to set up their Outlook profile again, but this will setup Outlook for 365. If they need access to their old mailbox get them to use OWA in the interim until the delta sync has been imported. There will be some delay and possible issues with the PST's do not export out cleanly, but that would be your best bet. I'd still try to see if you can set up a supported Migration scenario if possible. 

  • StefanKi's avatar
    StefanKi
    Iron Contributor
    Jul 28, 2020

    Hi HidMov 

     

    thank you for your answer.

    How can I create an online mailbox (step 2) for the users?

    In the UI of O365 I get this message

     

    This user's on-premises mailbox hasn't been migrated to Exchange Online. The Exchange Online mailbox will be available after migration is completed

     

    in step 3 I want to change the MX records. But for step 2 I already need the mailbox for the users in Exchange online. The users should use this online mailbox only after step 2 is finished until then they should use the onpremise mailbox.

     

     

     

     

    • DeepakRandhawa's avatar
      DeepakRandhawa
      Iron Contributor
      Jul 28, 2020
      run below and assign licenses and you should be able to create mailboxes in O365 :-
      Set-User Jon@contoso.com -PermanentlyClearPreviousMailboxInfo
      Ref:- https://techcommunity.microsoft.com/t5/exchange-team-blog/permanently-clear-previous-mailbox-info/ba-p/607619

      also you can set up mailflow connectors between on-prem and O365 and migrate users in batches, below article explains how you can set up a criteria based mail routing:-
      https://help.bittitan.com/hc/en-us/articles/115008260168-How-do-I-set-up-mail-routing-on-Office-365-when-migrating-users-in-batches-
      • StefanKi's avatar
        StefanKi
        Iron Contributor
        Jul 28, 2020

        Hi DeepakRandhawa 

         

        thank you for your answer.

         

        Do I have to stop AD Connect and make changes to the user before?

        Set-User Jon@contoso.com -PermanentlyClearPreviousMailboxInfo

        Output with AD Connect activated

        The command completed successfully, but no settings of 'Jon' were changed.