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Happy twentieth birthday, PST format

Nov 16, 2016 by Thomas Madsen

And happy retirement to all those PSTs still out there
The PST format started out in 1996 as a great idea. But as it reaches its 20th birthday, we decided to take a look at why PSTs should be heading straight towards early retirement.
[vc_column width=”1/4″][vc_column width=”3/4″]If you want to know how long ago PST files were introduced, just look at how young Bill Gates looks here.When Microsoft tried to own the internet
Fresh from the launch of Windows 95 (take a look Bill Gates’s extraordinary celebratory dancing here), 1996 was the year Microsoft waded in and tried to own the internet.

Microsoft Windows, Word and Excel had already taken over the desktop. But there was also an estimated 45 million users of this new-fangled ‘internet’ thing – and each one was a potential Microsoft customer.

Microsoft launched a two-pronged attack in 1996 with Internet Explorer 3 and its bundled ‘Mail and News’ tool (later Outlook Express), along with Exchange Server and Exchange Client (later Outlook) for corporate email. The Exchange/Outlook ecosystem arrived and dominated the corporate market. And with every client installation came at least one PST file.

Well over three billion people use the internet today, and for many of them their experience of network computing and email has been shaped by Microsoft. So in a way, maybe Bill Gates succeeded in leaving his mark on the internet after all.

The longevity of PSTs
In 1996 the idea of ‘always on’ internet sounded very futuristic. In those days, even private networks were bandwidth-constrained and unreliable by today’s standards. So by default, all Exchange/Outlook client installations created an unsynchronized format called the ‘personal storage table’ (PST) file on every local machine to manage users’ data. It meant users could choose to work from local files (or, in many cases, they were instructed by their IT departments to do so) to make sure that expensive or flaky bandwidth and storage wasn’t overloaded.

Other than TXT files, not many other file formats have survived unchanged and are in common use to the present day. The reality is PSTs have grown and grown as users manipulated, duplicated and backed up their own files.

Today, many organizations are still sitting on terabytes – and sometimes petabytes – of unmonitored critical, sensitive data contained in PSTs on file servers, laptops, desktops and USB sticks.

Why PSTs are not welcome anymore

Do you still have PSTs?

The answer to this is undoubtedly ‘yes’ – unless you’ve already knowingly undertaken a systematic program to eradicate them.

Second question – why should you get rid of them?

There are countless reasons not to use PSTs. They don’t work with modern client architectures, VDI or mobile environments. They’re portable, susceptible to data leakage, poorly protected from hackers, wide open to malware, and easily corrupted. You can’t centralize or manage them, or even track how many exist across the organization. Vitally, you can’t enforce retention policies as you have no control over PSTs, making you highly exposed from a legal, regulatory and compliance perspective.

But we would say that, wouldn’t we? After all, Quadrotech is the developer of PST Flight Deck, the number one automated finder and eradicator of PSTs.

In actual fact, it doesn’t matter if you use our tools, someone else’s, or whether you attempt the near-impossible challenge of hunting down your PST files yourself – confronting the problem is crucial. Data from old PSTs needs to be processed and absorbed into your new email ecosystem before zapping all PSTs out of existence.

Interestingly, the danger typically comes from older PSTs that are scattered around your business, rather than files that are actively in use. Most organizations have moved to newer versions of Exchange Server or to Office 365, where ‘always on’ access is taken for granted, and only a small amount of cached data needs to be stored on the local device.

An alternative vision of the future, from 1996
In 1996, the same year the PST was born, a new approach – web-based email – made its first mainstream appearance. Hotmail needed no local software other than a browser (at the time, typically Netscape. Microsoft soon saw that off, too).

If we had had mobile devices back then, Hotmail would have been accessible on anything from anywhere. Exchange, by contrast, was restricted to those in the office or the few execs that connected remotely on their laptops.

Was Hotmail the true future of email? Microsoft hedged its bets and bought Hotmail in 1997 (well, when owning the internet is your master plan, you don’t want to take any chances).

Hotmail subsequently went through a number of iterations – MSN Hotmail, Windows Live Hotmail, and eventually – and the service is now delivered as part of the Office 365 cloud-based infrastructure. Microsoft hasn’t published any updated user numbers since 2013, when it had 400 million users but, taking the corporate and consumer base into account, there must be a very impressive user base active in 2016. It’s clear that cloud-based email with central management capabilities is the present, whether this will still be the case in another 20 years remains to be seen.

Blowing out the candles – one final use for the PST
Enough of this PST-bashing. We will end the birthday toast by celebrating the one last trick it has up its sleeve.

If you’re going to migrate email data to another platform (e.g. Office 365 or an archiving system), you need to consolidate, filter, de-dupe and track everything you have. The PST file’s final redeeming quality is that it can act as a single file repository to transfer that information to the new platform. Essentially, the PST helps you with the final part of its eradication.

Bill Gates was certainly onto something when the PST file first came about, but it’s clearly had its day and we wish it a long and happy retirement.

Want to know more?
Download a copy of the independently-written and edited Complete Guide to Eradicating PST Files at Amazon: