How do I migrate large mail items to Office 365?

Follow

Comments

8 comments

  • Avatar
    Jason Wagner

    You can change the default for an organization by adjusting the default message size restriction. In the Exchange admin center Simply select recipients mailboxes then click “. . .” and select Set default message size restrictions.

    Office 365 now supports larger email messages 1 v2
    You can then specify the maximum message size for new mailboxes (only for those you create in the future).

    For existing users...

    To edit multiple mailboxes select recipients > mailboxes and select multiple mailboxes. Then from the Bulk Edit pane under Message Size Restrictions select Update.

    Office 365 now supports larger email messages 3 v2

    You can customize a single mailbox by selecting recipients > mailboxes and then select a user’s mailbox. Click the edit icon , then under Message Size Restrictions, click View details and then specify the maximum message size.

    Credit due to: https://blogs.office.com/en-us/2015/04/15/office-365-now-supports-larger-email-messages-up-to-150-mb/

    1
    Comment actions Permalink
  • Avatar
    Georgiy Frolov

    After following the guide - "Connect to Office 365 PowerShell" from Microsoft listed in this KB article, you need to follow additional guide - "Connect to Exchange Online PowerShell"  to be able to execute those PS commands, otherwise you will get errors from PowerShell such as "The term 'Get-Mailbox' is not recognized as the name of a cmdlet, function, script file, or operable". 

     

    5
    Comment actions Permalink
  • Avatar
    Mark Keller

    Life saver Georgiy Frolov !

    1
    Comment actions Permalink
  • Avatar
    Upward Technology

    Gregoriy FTW.

    Thank you.

    1
    Comment actions Permalink
  • Avatar
    Eden Freeman

    MaxSendSize: 150 MB (36,700,160 bytes)
     
    MaxReceiveSize: 150 MB (37,748,736 bytes)

    Those numbers don't match up.

     

    Also, it seems like this does not modify existing mailboxes, only new ones created with that plan/policy.

    https://docs.microsoft.com/en-us/powershell/module/exchange/mailboxes/set-mailboxplan?view=exchange-ps

    Modifying the settings in a mailbox plan doesn't affect existing mailboxes that were created using the mailbox plan. The only way to use a mailbox plan to modify the settings on an existing mailbox is to assign a different license to the user, which will apply the corresponding mailbox plan to the mailbox.

     

    0
    Comment actions Permalink
  • Avatar
    Kyle Rinner

    I will have the KB updated so it shows the correct numbers:
    MaxSendSize : 150 MB (157,286,400 bytes)
    MaxReceiveSize : 150 MB (157,286,400 bytes)

    You are correct, the command "Get-MailboxPlan | Set-MailboxPlan -MaxSendSize 150MB -MaxReceiveSize 150MB" does not modify mailboxes that already exist.
    The next command will modify the max size for all existing mailboxes: "Get-Mailbox | Set-Mailbox -MaxReceiveSize 150MB -MaxSendSize 150MB"

    0
    Comment actions Permalink
  • Avatar
    McChan Rawson

     

    From Frovlov

    "After following the guide - "Connect to Office 365 PowerShell" from Microsoft listed in this KB article, you need to follow additional guide - "Connect to Exchange Online PowerShell"  to be able to execute those PS commands, otherwise you will get errors from PowerShell such as "The term 'Get-Mailbox' is not recognized as the name of a cmdlet, function, script file, or operable". 

    Actually you don't even need to follow the Connect to Office 365 PowerSehll guide you just need to do the Connect to Exchange Online Power Shell link and follow those directions to get this done.  Also don't really need the first command as its just to check the current size and also can be used after to verify results as well.

     

    1
    Comment actions Permalink
  • Avatar
    Jeremiah Benes

    I'd recommend updating these steps to address connecting to Exchange Online when multi-factor authentication is enabled. Microsoft has instructions online.

    1
    Comment actions Permalink

Please sign in to leave a comment.