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FACT: If you migrate legacy shortcuts into Exchange Online, it’s highly likely they’ll ‘still work’ if your archive remains on-premises

If you move shortcuts along with regular emails as you migrate mailboxes to Office 365, nine time out of ten they will still work: 

That is to say, when you double click on the shortcut, the original full email will be retrieved across the network from the on prem archive.

For example, with Enterprise Vault (EV), a user can still recall/retrieve old, archived email items using EV shortcuts. They can also use the EV Search service to access and search their archived emails as part of integrated search within the Outlook client or via a web URL in a browser.

The downside is that post-migration:

  • you can’t archive anything new in EV 
  • you can’t use web access to access the shortcuts (as Veritas doesn’t control the OWA servers)
  • end users cannot restore or delete archived email items from shortcuts

Other archive vendors may behave similarly.

There are a number of other downsides:

It’s unsupported

Microsoft won’t support this set up – why should they?  As indicated above – the archive vendor cannot control the Microsoft environment and will therefore be limited in what it can offer.

Over time, your on-prem archive will become unreliable and expensive

“Although shortcuts to archived emails would still work across the network after we migrated to Microsoft 365, the prospect of maintaining a dedicated email archive on-premises was a non-starter.  The SAN it used was becoming increasingly unreliable and the overheads of maintaining it were costly.”

According to Stephen Appleby of An Post, the state-owned provider of postal services in the Republic of Ireland, “Although shortcuts to archived emails would still work across the network after we migrated to Microsoft 365, the prospect of maintaining a dedicated email archive on-premises was a non-starter.  The SAN it used was becoming increasingly unreliable and the overheads of maintaining it were costly.”

Not surprisingly, COVID-19 has also highlighted the challenges of maintaining and backing up systems that are sitting in a server room in the office.

Annual software maintenance and support costs can also escalate, and high costs don’t necessarily mean you get a high-quality service in return. 

For example, EAS, one of the first email archiving solutions on the market, has effectively ‘changed hands’ five times (from Educom – Zantaz – Autonomy – HP – Capax ….. ) Other solutions have become similarly acquired and/or merged into an existing portfolio, with each change risking an uncertain roadmap and lack of focus on development and support from the new ‘owner’.

You’ll have a separate place in which you’ll need to manage retention and eDiscovery

On-premises archives (and to some extent, hosted archives) are of a ‘technical’ nature when it comes to implementing retention policies and performing eDiscovery. 

It’s likely the IT department will still need to manage retention policies and do eDiscovery. 

We frequently encounter IT teams that spend hours responding to eDiscovery requests.  For example, a client using EAS found its eDiscovery service was simply not up to the job for the volumes they had, with searches taking hours and hours to execute.  The suggestion on the part of the archive vendor was to beef up the IDOL search servers available – something that would have been prohibitively expensive.

Likewise, the job of implementing retention policies typically falls on the shoulders of the IT team, with little guidance on deletion policies from the legal department.

The great news is that Microsoft 365 offers a compliance and eDiscovery capability that is becoming super-user-friendly, to the point that you can now shift responsibility for compliance-related activities OUT of the IT department.

The other big benefit of moving the contents of legacy archives into Microsoft 365 is that you can perform eDiscovery in one location.  Having multiple different locations to search and then reconcile introduces both time and risk, which brings us onto the next issue:

Ultimately, is it worth having a separate archive?

Those in the business of providing dedicated email archive services would, of course, argue for the need to have a separate archive in the cloud.

For example, there are Veritas partners that offer services to host the storage component or your entire EV environment in Azure.

Also some vendors offer a cloud-based version of their previously on-premises archive.  For example, you can migrate EV into Veritas’ hosted service, Enterprise Vault.cloud.

There are also hosted archiving services from organisations like Mimecast and HubStor (now part of Veritas).

This is where the blurring of the boundaries between archiving and backup come into play and that is a separate subject again.

Another factor with each of these approaches is that they require some form of change on the end-user’s view – i.e. the concept and convenience of shortcuts goes away.

Why you should move your archives to Microsoft 365

Unlimited capacity

The storage capacity benefits of using a separate archive have fallen by the wayside with Microsoft 365.  There’s very few email users whose mailbox and historic archives can’t be accommodated by Microsoft 365 licencing:

  • A Primary Mailbox can grow up to 100GB (E3 and above)
  • An Archive mailbox in theory has no cap on it

No charge for leavers

If you have archived mailboxes belonging to leavers, you can take advantage of inactive mailboxes and place them litigation hold (or specifying an appropriate retention policy) to retain their emails indefinitely (or as required) without incurring a licence penalty.  

The average ration of ‘leavers’ to ‘current staff’ archive mailboxes in the typical archive can be as much as 4:1, so this amounts to a significant cost saving.

Advanced Compliance Capability

As we said earlier, the compliance and eDiscovery capability now available in Microsoft 365 is ‘up to the job’ of handling most information requests and data protection needs.  Importantly – Microsoft’s trajectory is to provide services that don’t need as much input from the IT department.

If that is enough to compel you to shut down your on-prem or hosted dedicated, third-party archive completely and, ideally, get the contents of your archive into Microsoft 365, this is what you need to know:

Successfully migrating email archives into Microsoft 365 requires care (there is no real shortcut)

Migrating the contents of a legacy archive into Microsoft 365 is a speciality for Essential and something we’ve been doing since 2005.

One thing you’ll discover is that there are a few different routes you can take.  

For example:

  • Do you migrate shortcuts into online mailboxes using mailbox moves, and then replace them with the corresponding archived item later?
  • Do you migrate archives first?
  • Where do you put emails that users have deleted from their archive (but are still in the archive)?
  • How do you treat mailboxes that are too big according to Microsoft’s licencing rules and throttling measures?  This can become an issue when you ‘re-hydrate’ a shortcut with a much bigger archived item.
  • What about shared mailboxes, public folders and journal archives?

The answer to each of these questions will vary depending on a lot of things, including the capabilities of the archive you’re moving from.

For example, HP ACA and AXS-One are archives that need extra care and steps to ensure the best compliance and end user outcomes

“Essential worked out the best strategy for migrating our archived emails into Exchange Online.  We received top notch documentation from Essential’s consultant, Toni Mallin, and this enabled us to complete our own migration with very little assistance.” 

According to An Post, whose legacy archive used HP’s ACA (Autonomy Consolidated Archive), “Essential worked out the best strategy for migrating our archived emails into Exchange Online.  We received top notch documentation from Essential’s consultant, Toni Mallin, and this enabled us to complete our own migration with very little assistance.” 

As with An Post, the cost of a migration is always a consideration and we are able to offer a service that enables your IT team to easily oversee elements of the migration and reduce costs.

One thing for sure is that the cost of migration will be significantly less than maintaining an on-prem archive and performing countless eDiscovery searches.

Find out more about our email archive migration services.

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When going through an email archive migration, understanding the way your end-users work with their archives is worth getting to grips with, otherwise you could be heading for a bumpy ride.

A long while back we worked on a migration where we took our client’s request at face value:

Just migrate the last 6 months’ worth of email archives into the cloud”.  And so we did.

Well, let me tell you, the staff at the organisation in question kicked off big time when they realised what had happened.

In short, the decision to migrate this limited amount of data was made by the IT and compliance teams ‘in isolation’.  By that, I mean the end users themselves were not consulted on what they needed and what was happening: they just arrived on Monday morning to discover anything older than 6 months was gone.

The upshot was we had to re-run the migration to move many years’ worth of users’ emails.

Always consult end users

The moral in the story is, when you migrate your archived data, making technical and/or compliance-only-led decisions about what gets moved can lead to huge productivity hit on the business.

So how do you make sure your migration is also user aware?

To ensure your migration is truly user – or dare we say – business-aware, a key thing to bear in mind when you make plans to move archived emails to a new platform is: “What types of email users you have in your organisation.”?

Over the years we’ve encountered 4 main types of users:

First up: ‘The Filer’

These super-organised users put everything into the right folder.  This could mean moving things several times to ensure they can instantly locate what they need to do their job.

filer user aware email archive migration

Something to check before you migrate:  If your archive isn’t fully synchronised with the latest shortcut locations, emails could get migrated to the wrong folders.

Next, the Sharer

Sharers make a habit of forwarding useful emails to co-workers or putting them into public folders.  They’re a vital component in building on your enterprise knowledge resource.

sharer user aware email archive migration

Beware:  It’s highly likely folk that used to have access to ‘shared’ archived emails will lose out when you migrate, as many archives don’t store this type of information.


They are the ‘dream’ end user in many ways, as they systematically get rid of what they don’t need or what they have already dealt with.

deleter user aware email archive migration

Watch out:  Again, if your migration path does not synchronise up with what users have deleted from their view of the archive (and bear in mind that even the best archives can ‘miss’ deletion activity), you risk having stuff re-appear for end-users post-migration – which will freak them out.


They tend to be less disciplined in their filing and rely heavily on their archive search service to find past emails.  They’ll often delete emails safe in the knowledge that they’ll still be able to hunt them out later.

Searchers user aware email archive migration

Caution:  If you have a lot of this type of user, you won’t get away with using filters or doing a stub only migration.


Migrating to Office 365 or another new platform should be a stress free experience.

By paying attention to the types of end-users you have, and not under-estimating their reliance on access to archived email, you can ensure a seamless transition, where:

  • Emails end up in the right folders post-migration
  • Data that has been shared is still available post-migration
  • 1000’s of previously deleted emails don’t suddenly reappear back in users’ Office 365 mailboxes
  • Years’ worth of past reports, proposals, papers, technical responses, orders, etc., are still accessible.

Migrating to Office 365 or another new platform should be a stress free experience

For more tips on best practices for email archive migrations, get in touch.