How do I migrate large mail items to Office 365?




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    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:

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    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". 


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    Mark Keller

    Life saver Georgiy Frolov !

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    Upward Technology

    Gregoriy FTW.

    Thank you.

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