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.psts are like vermin.

Experts agree they are a pest and IT departments across the world are all too familiar with the support nightmares they create. They also carry the risk of data loss & exposure.

Apart from being massively out-of-control in most organisations (difficult to locate on users’ hard disks and containing unknown evils), they are inherently difficult to grapple with.

Having worked on PST elimination projects for over fifteen years now, we have encountered quite a few challenges and gotchas.  Here’s just a few to bear in mind if you are planning to get rid of your PSTs.

1. Users Get Attached to their PSTs

Having been forced to use PSTs for so many years to stay within enforced quotas, end users have become used to them ‘being there’.  We know of law firms whose partners have created PSTs for each major client, and store them on their laptops.  Removing PST files without explaining why; and without creating a familiar and easy way to access the contents of PSTs post migration, will be very dimly received.

2. PSTs are only accessible by one user/application at a time

PSTs are only really designed to be accessed by one user or application at a time. This creates a challenge where PSTs are opened when a user logs into Outlook.    If this happens as a matter of course at your organisation you will need some way to ensure users don’t access their PSTs during your migration project (see also next point).  You will also have to work out how you are going to tackle users with laptops that only connect to the network intermittently, and users that always have their PSTs open.

3. PSTs are usually an ‘all or nothing’ thing

If you look at a PST in a directory listing – it’s just one file.  It’s effectively a container file, and with most solutions that you can use to move or eliminate PST contents, you’re typically looking at taking the whole file with you.  This can mean taking a whole bunch of stuff you just don’t need or that falls outside of your retention policy.  Having said this, it’s possible to take a more granular approach and just select the items you want to move according to different criteria.  We have found this saves a lot of time and network bandwidth (as well as archive storage).

4. PSTs might be changing all the time 

If you plan to tackle PSTs we recommend you create an Outlook Group Policy that makes the existing PSTs read only and prevents new PSTs from being created.  This will put your PSTs in a ‘stable’ situation while you are tackling them.

5. Be Careful Assigning Ownership

From a legal and audit point of view, who owns a PST file can be vital information. Where PST files are stored on network shares it might seem to be obvious who the owner is, but this depends on how structured the shares are and permissions on each folder within the share. Where “team” folders exist, each PST file could contain messages which are “owned” by several people. Where PST files are stored on desktops then you need to examine what happens when one user leaves and another joins. Are the desktops completely rebuilt or just new profiles configured? In the latter case PST files could be lurking that belong to users who have left the organisation many moons ago!

6. What happens post PST removal?

Users who are working offline will tend to have PST on laptops.  Using Outlook in cache mode (which creates an OST file) is the logical alternative for enabling offline access, so following a PST migration exercise you need to make allowance for the extra network traffic that will be created during the first offline synch after migrating them.

There are many more PST tips we have

Get in touch and find out more about our PST migration services.

Even though Microsoft offers free tools to import your PST files into Microsoft 365, does anyone really relish the thought of migrating ALL of their PST files into Exchange?

Probably not, because:

  1. You end up moving old rubbish
  2. It will pound your network
  3. Users might not like it

Having worked with hundreds of customers to roll-out email archives, PST migration is always the painful final phase that often gets brushed under the carpet for the aforementioned reasons.

The over-arching requirements for anywhere, any device data accessibility and centralised data governance, however, may be the final nudge to get your PST migration project management backing.

So is it acceptable to filter out the rubbish before you siphon it into your shiny new Exchange environment?

At the very least it’s surely prudent to get a policy agreed that will define your PST migration including whether to migrate:

  • Content that outdates your email retention policy
  • Folders marked ‘Personal’
  • Content that pre-dates your switch on of Journal capture
  • Duplicate PSTs

A PST migration project means bracing yourself for decisions about what to migrate and no-one likes decisions! But we like the advice from Craig Ball, a Texan trial attorney and certified computer forensic examiner:

‘To Preserve broadly is safe, but expensive. To Preserve carefully is safe and cost-effective”.

The truth is, any enterprise-level PST migration exercise – even if you gather up everything – is not easy and you may struggle with free Microsoft tools.

PST Migration Challenges

Check out the top 6 PST Migration Challenges