Back to blog

Email archiving in Exchange Online – What do you need to know?

Jan 17, 2017 by Emma Robinson

Office 365 and archiving
Email archiving is a systematic approach to saving and preserving data contained in email messages so it can be searched and accessed at a later date. Most organizations of a reasonable size are likely to need a compliant archive solution.

If you’re a smaller business just starting out with Office 365 you may wonder why you should bother with an archive at all. With 100GB mailbox limits now the norm on plans E3 and above, the previous compelling reason of optimizing storage isn’t really an issue any more. If conditions were right, you could theoretically just migrate your email archives straight into your primary Exchange Online environment.

While this may seem like a tempting option, archives can still be needed. They are necessary for regulatory compliance, and protection against litigation, making them a ‘must-have’ for industries that are highly regulated (like finance and healthcare), and a recommended strategy for organizations operating in other sectors. Having well-defined retention policies and a good archiving system makes it easy to enable ‘legal holds’ ahead of expected actions.

Legal hold:  An instruction within a business organization directing employees to preserve, and refrain from destroying or modifying, certain records and information (both paper and electronic) that may be relevant to the subject matter of a pending or anticipated lawsuit or investigation.

During this process, electronic documents and correspondence must be retrieved as evidence using ‘eDiscovery’. No one can predict what data you’re going to need to retrieve in six years’ time¸ so in order to comply with this process in any eventuality, your archive strategy has to be far-reaching and extensive enough to deal with these requests, if and when they happen.

As a rule, larger businesses historically used on-premises systems such as Symantec/Veritas Enterprise Vault (EV), Dell Archive Manager, or EMC EAS, while SMEs were attracted to cloud-based archiving services such as Mimecast, Iron Mountain or Enterprise

Migrating to Office 365 is an opportunity to review your archiving solution – particularly because you may have to make changes in order to ensure compatibility; for example, old EV shortcuts – or ‘stubs’ – don’t work in Office 365. The security and compliance features available in Exchange Online are intelligent and robust, and with the huge amounts of secure, low-cost storage available, it can make operational and economic sense to look at migrating the entire email ecosystem onto the platform.

So, migrating your email archive into Office 365 seems to make financial and operational sense – but what can you expect? What’s new, and what’s familiar? Let’s take a closer look at Exchange Online Archiving.

How do I get Exchange Online Archiving?
Exchange Online Archiving (EOA) is an evolution of what was formerly known as Microsoft Exchange Hosted Archive. Starting out as a cloud-based archiving service much like any other, the system was designed to work in conjunction with on-premises Exchange installations and so is compatible with Exchange Server 2010, 2013 and 2016 as well as Exchange Online as part of Office 365.

EOA is automatically included free of charge in Office 365 E3-E5 plans, and is available as an optional add-on to other plans using a per-user, per month subscription ($3 currently).

Mailbox and archive limits and options in Office 365 plans[vc_single_image image=”4994″ img_size=”large”]*Each subscriber initially receives 50 GB of storage, though this can be increased. The Office 365 Roadmap indicates that Microsoft intends to automatically extend storage as needed on these plans.

EOA creates what is known as an In-Place Archive, which can be accessed by a single user or entity (such as a shared mailbox) with an appropriate Outlook license, just like any other archive. There’s no need to grapple with a separate interface to manage archived items. People can view messages in their archive mailbox and move or copy messages between their primary and archive mailboxes.

Retention policies help users organize their information by enabling them to archive or delete items at their discretion. By default, after the archive mailbox is enabled, items that are two years or older get moved from a user’s primary mailbox to their archive mailbox, and items that are 14 days or older (from the ‘Recoverable Items’ folder in the user’s primary mailbox) get moved to the corresponding folder in their archive mailbox. If you have created a retention policy in Exchange Online, messages will be automatically moved to a user’s archive mailbox if the user’s primary mailbox is larger than 10 MB.

Enabling and managing archive mailboxes
You can use the Exchange admin center (EAC), the Office 365 Security & Compliance Center, or Windows PowerShell to enable archive mailboxes. The advantage of Windows PowerShell is that you can quickly enable the archive mailbox for all users in your organization rather than undertaking the tedious process of doing this individually.

Differences between EOA and traditional archives
Third party systems such as EV create shortcuts within Outlook to items in the archive repository, whereas with EOA, the user is directly accessing the item itself. In fact, the differences between Exchange Online’s primary mailbox and archive mailbox functionality are relatively minimal (one notable change is that the archive doesn’t get cached in the local user’s offline storage table (OST) file).

What’s more, features like legal hold and eDiscovery work exactly the same in Exchange Online whether the primary or archive mailbox is being interrogated. If you put a litigation hold on the primary mailbox, the corresponding archive automatically assumes the same status, for example. This tight-knit integration makes it easier and faster to search archives, rather than having to trawl through a separate system.

Third-party archiving solutions do, however, contain some additional features that may be required by the most highly-regulated or complex organizations. For example, if you use other email systems (such as Gmail) alongside Exchange, or if you need to archive instant messaging data from other platforms, you may want to look at what they offer, and evaluate the additional benefits against the potential extra cost. The best fit really depends on what your organization needs from an email archiving solution – but given the breakneck speed of Office 365 product development, you may not have to wait long until the platform catches up with other third party solution’s feature sets.

ArchiveShuttle is an industry-leading archive mailbox migration tool. It automates the extraction and ingestion of data, and eliminates risk with backups and data integrity checks. Huge volumes of data can be transferred, and users have uninterrupted access to their data. Find out more.