Microsoft has launched a preview of its Office 365 Import Service, which allows customers to upload or post discs to Microsoft to move data to its cloud services.

The preview is available to a broad range of Office 365 customers that need an efficient way of migrating huge volumes of content -- for example, terabytes of email in the form .pst files -- to Microsoft's services Office 365, SharePoint Online, and OneDrive for Business.

It follows a limited public preview in May that was made available to Office 365 Commercial, Office 365 Education, and multi-tenant Government Pricing customers, but not Office 365 Dedicated or Office 365 Government Community Cloud customers.

Since 2013, Microsoft has let customers in the US, Europe, and Asia post their encrypted hard drives to move large amounts of data in and out of its different Azure regions using its Azure Import/Export service. The service functions as a temporary holding place for data before it's migrated to SharePoint Online and OneDrive for Business.

The Azure import/export service is similar to services offered by Amazon for AWS and the postal option Google recently added for its US Cloud Platform customers.

The Office 365 Import Service is aimed at businesses that want to improve compliance and data recovery by moving email and documents from company desktops to the cloud.

"When you upload your data or ship your drives, the data is temporarily staged within Microsoft Azure until it is imported into SharePoint Online and OneDrive for Business," Microsoft said.

"All hard drives are encrypted with BitLocker protection, and the BitLocker key is sent separately from the drives. This protects them in the event they are lost or stolen in transit. If you choose to physically ship hard drives to Microsoft datacenters, they will be returned to you once the data has been imported," it added.

Besides the courier option for the preview service, Microsoft says it has improved procedures for using the network to migrate to SharePoint Online, thanks to its new Migration API, though that option is recommended for smaller migrations. Customers that need to move more than 10TB of data will find drive shipping is faster, says Microsoft.

Microsoft has already switched on the service in the US but still hasn't enabled it for Office 365 Dedicated customers and SharePoint Online hosted in its Brazil, China, Japan, or Australia datacentres.

For now, as a preview, the service is free though Microsoft will be charging for it as a separate Office 365 when it is made generally available.

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