Office 365 Import Service released

The newly announced Office 365 Import Service has been released for Office 365 customers joining the First Release program. You can read more about the new improvements in First Release in my blog post Fine tuning option available for “First Release” in Office 365

To ensure compliance, information discovery and protection, most of the organizations I am working with, moving to Office 365, are focused on getting all message data, for the migrated mailboxes, consolidated in Exchange Online. But, Office 365 migrations are often not a trivial process, and for organizations moving to Office 365, getting the archived mail and PST files along can be a challenge.

Luckily, we have the PST Capture Tool, which provides an excellent assistance, and can be utilized for both discovery and upload to Office 365, in situations where PST files are scattered across network locations and devices.

Still, moving 10’s or even 100’s of Terabytes of message data to Microsoft data centers can place a significant load on the corporate WAN connections and make the process a lengthy endeavor.

Microsoft introduces a new service called the Office 365 Import Service, which basically addresses two scenarios:

  1. Upload data to Office 365
    When migrating smaller or medium amounts of message data (<10TB), the Azure AzCopy tool can be used for copying PST files from an on-premise repository, securely across the Internet to Azure where a back-end service import the data into Exchange Online mailboxes.

    Office 365 Import Service - upload

  2. Ship hard drives to Microsoft
    When migrating larger amounts of message data, the Azure Import/Export Tool can be used for preparing physical hard drives, where PST files are then copied to, from an on-premise repository. Using approved carriers, the hard drives are shipped directly to the regional Microsoft data center, where the PST files are first copied to internal storage and later imported to Exchange Online mailboxes.

    Office 365 Import Service - Ship

The Office 365 Import service utilizes the Azure Import/Export service, which has been available for the last year and enables customers to transfer large amounts of data to or from Azure Blob storage. From the Office 365 Import Service, the data is loaded into the Azure file storage and from here imported to Exchange Online mailboxes.

Accessing the Office 365 Import Service require either Global Administrator role, or an Exchange admin role which include the Mailbox Import Export role. A new Exchange admin role can be created in the Exchange admin center -> Permissions -> Admin roles -> New (the ‘+’ sign).

Mailbox Import Export admin role

Access the Import Service from Office 365 Admin center -> Import

Office 365 Import Service

Requirements for network upload:

  • PST files must be collected and prepared for upload.

Requirements for hard drive shipping:

  • The message data on the shipped hard drives must be stored in PST files
  • Only 3.5 inch SATA2 and SATA3 drives are supported.
  • Hard drives must NOT exceed 4TB size or have multiple volume, as only the first volume are processed.
  • Data volumes must be formatted with NTFS.
  • To ensure data privacy during transit, the shipped hard drives must be protected with BitLocker drive encryption
  • The BitLocker key must only contain numerical characters and must be sent separately from the hard drives.
    • Later, the option to use Azure RMS protection on the shipped files should be made available.
  • Use FedEx or DHL as carrier of the hard drives.

Requirements common for both methods;

  • An active Office 365 subscription with active users and mailboxes for all users where PST data must be imported.
  • A file with PST-to-user mapping information.

Format of the PST-to-user mapping file:


During the preview, the Office 365 Import Service will have no change. So far no GA pricing details has been public announced.


More information on TechNet:

Office 365 Import Service

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