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Avoid costly email migration project mistakes

Sep 22, 2015 by Romulo Melillo

A holistic view from the outset can save time and money

There are plenty of good reasons to migrate email to Office 365. These reasons include compliance, functionality, security, cost savings (and many more that each justify their own blogs). But there’s a natural inclination among some organizations to be over-cautious in project execution – and that can cause problems further down the line.


One of the most common pitfalls we’ve encountered in over ten years helping customers migrate their email ecosystems is that they often treat the ‘triple stack’ of live mail, archives and local PST files as completely separate problems. There are several reasons for this:

  • It’s normal practice to break large projects down into discrete sub-projects that are run consecutively rather concurrently.
  • It’s theoretically easier to allocate resources to separate sub-projects.
  • It’s easier to make a business case and to obtain a budget for smaller projects.
  • There’s a compelling business priority that ignores the rest of the email ecosystem (e.g. live mail needs to be migrated to Office 365 as part of a technology refresh).
  • Email migration is driven purely as an IT project.

You might think it makes sense to obtain appropriate tools when required, and to treat each aspect of the stack sequentially. But where do you start? As soon as you move live mail, archives or PSTs by themselves you risk breaking dependencies within the ecosystem. That, in turn, raises new compliance issues. Once underway, the whole thing can be expensive and time-consuming to put right, and most organizations eventually give up and migrate all three components anyway.

An integrated approach, with good forward planning, can reduce cost and speed up the migration process, and deliver business benefits faster.

What’s the problem with dependencies?

As an example, let’s look at Exchange Vault (EV) shortcuts. EV is a popular archiving solution; the theory is that you remove older files from the live email environment (e.g. Exchange) and put them on slower, cheaper storage managed by EV. Where many users have been copied on emails, or where there are large attachments, EV de-duplicates and intelligently indexes the contents as single instances to save space.

Users only notice the difference between live mail items and those that have been archived into EV because the icon has changed in Outlook. That icon is only a shortcut, pointing to something stored within EV. If the user clicks on it – to view, reply or forward – there’s a momentary lapse while EV responds and the item appears as normal. It’s a near-seamless user experience.

The problem? The moment you move either the legacy archive or live mail, you break that link. It’s not an uncommon problem, particularly when migrating to Exchange 2013, as noted by one system administrator here. The problem is even worse with cloud email services; Office 365 doesn’t recognize EV shortcuts at all.

PST dependencies

The dependency problem is even worse when users are also running local PST files (in most organizations they are, though users probably don’t know that). Our EV shortcuts get copied, moved, deleted and duplicated in ways that are impossible to track. They become viral as they are forwarded and copied.

By default Outlook regularly prompts users to auto-archive old email to PST files. More literate users will not only follow the instructions but also may even manually create or tinker with their PSTs. Whatever the reason, as soon as you move your archive the PST shortcuts break.

Legal and regulatory issues

If your email ecosystem isn’t properly connected it becomes very difficult to demonstrate compliance and to retrieve items to defend lawsuits. Since Exchange Online 2010, Microsoft has built compliance tools into its system. It has some clear advice on how to manage retention and discovery in Exchange Online and Office 365, for example.

Of course, this approach only works if your email ecosystem is migrated as a whole. Our experience is that legal officers intervene as soon as they discover only part of the email ecosystem is being migrated, partly because everything else might remain non-compliant but also because they know piecemeal migration poses new, direct compliance risks.

Faster, safer migration across the board

Live mail, archives and PSTs all present their own difficulties, and when planning email and archive migration our advice is to expect the worst. Assume you will need to lift the whole stack at the same time, and then test that theory to see if anything will break if you defer one aspect. Make sure you get advice from your compliance team about their expectations and the effect of migration on existing and future retention policies.

If it turns out you can safely migrate one element without any detrimental effect, that’s great news. But in many organizations you’ll need to address two or three elements of the stack together, and it makes sense to plan a unified project.

Quadrotech is unique in having a proven migration toolset that can manage migrations across all three levels of the stack. For complex migrations, this approach simplifies the process, rationalizes costs and licensing, and ensures your objectives are met rapidly, safely and defensibly.