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Microsoft's Outlook Opens Up to an Uncertain Future

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ZA102633891033.jpg.gif.jpegWhile most of us were too engrossed in the somewhat ephemeral news of Google’s new attempts at becoming social, something much more profound transpired — something that can have an impact on millions upon millions of people. Microsoft (s MSFT) announced that it was opening up its Outlook format and giving external programs access to mail, calendar and contacts. I don’t know the reasons why Microsoft is taking this arguably high-stakes gamble.

Paul Lorimer, group manager of Microsoft Office Interoperability, wrote on the MSDN blog:

In order to facilitate interoperability and enable customers and vendors to access the data in .pst files on a variety of platforms, we will be releasing documentation for the .pst file format. This will allow developers to read, create, and interoperate with the data in .pst files in server and client scenarios using the programming language and platform of their choice. The technical documentation will detail how the data is stored, along with guidance for accessing that data from other software applications. It also will highlight the structure of the .pst file, provide details like how to navigate the folder hierarchy, and explain how to access the individual data objects and properties.

Now you might be wondering what, exactly, is new. After all, developers can access data stored in the .pst file using Messaging API (MAPI) and the Outlook Object Model — two ways folks such as Plaxo and Clear Context access information on your Outlook client. The only problem is that those methods are arguably very slow.

ClearContext CEO Deva Hazarika in an email writes:

The announcement makes it sound like this opens up a wide range of ways to extend what people can do with Outlook data. However, if people are actually using Outlook, those files are locked by Outlook and can’t be accessed without using the Microsoft APIs. And even if they could be accessed, I’m not sure what the value prop is in trying to write a better set of access methods than the APIs already in place. So, I don’t think this means very much for “live” instances of Outlook usage.

So far most of the details from Microsoft are very sketchy and it isn’t clear when the company will reveal its complete plans. To me it seems like Redmond was reacting to pressure from the European Union, which wants to push Microsoft down the road to interoperability.

Or perhaps it was somewhat of a late realization by Microsoft that it could turn Outlook into a platform. Blogger and technologist Anil Dash has argued about the potential of Outlook as a platform for a very long time. While many plugins have come to the market, many have argued that Outlook is not an easy platform to work on. It takes a lot of effort — ask Xobni — to work with Outlook.

I sought the opinion of Gabor Cselle, one of our favorite technology people and founder of reMail. In his past life he worked at Google (on Gmail) and Xobni, so he knows a thing or two about email. “The ability to upload PSTs is one of reMail’s feature requests,” he said, pointing out that it won’t really change things very much because much of the access is available via MAPI and OOM. “If anything this will make it easier to switch away from Outlook; for example Google could just ask you to upload your PSTs to switch to Gmail + Gcal,” he said. “That would be my use case No. 1.”

Deva agrees and points out:

In the past, if someone was moving from Outlook/Exchange to Gmail or any other platform, there was a pretty tedious process of exporting pieces of data from Outlook into various formats before moving over to the new platform. Basically, once you didn’t have Outlook, that .pst was a useless brick of data. Now in that case you’ll be able to take that .pst file with you and if other apps/platforms build readers, they will be able access that data. So migration to other platforms is a valid use case where there’s some benefit.

However, I don’t see this really doing anything to bring new capabilities for Outlook users to interact with a new generation of cloud services integrating with their Outlook data. That kind of innovation is going to keep going through the existing APIs within Outlook. This mainly seems to me like a marketing move to counter criticisms/fears about the closed nature of Outlook/Exchange data, but doesn’t really provide a ton of benefit to most end-users.

What do you guys think?

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16 Responses to “Microsoft's Outlook Opens Up to an Uncertain Future”

  1. Great article – this is an incredibly important move – one I think Microsoft should have done years ago. Whether it’s a good or bad move, I’ll leave that to others to decide.

    Here’s why its important – a major amount of mail data is stored in PST files today. If all of these millions of mail files were to to be openly accessible by the open source community and/or third party utilities – the possibilities could be endless – I’m talking ZIP endless, ZIP level of ubiquity. I’m sure that would afford Microsoft with a little more ROI than a dead mail client platform.

    It seems clear that the application that is Outlook is dying – heck, you could even say to an extent that the MS Office package is dying (or being forced to change). “Cloud” is becoming more pervasive and the lock-in that MS has with Outlook is being eroded daily by cheaper and better mail systems and clients (yes, even the Exchange/OWA is killing Outlook to some extent).

    The trick here is the storage platform, Microsoft has created a (somewhat) robust storage platform for mail/calendar/etc data that could be incredibly portable and useful in the futre. Have you ever used “Gmail Backup” or other types of mail archiving utilities? What you get is 6000 .eml files. Not exactly a robust storage solution. Imagine the PST becomes one of the de-facto standard for storing and transporting mail data or archiving this data? I think this is what Microsoft wants.

    Currently, PST data is hard to open, easy to move around but useless after being transported and can’t be open directly off a disc. Opening

    Kevin (@calwell)

  2. I’m pretty sure that I saw somewhere that MS was starting to move Outlook away from dependance on Windows specific tech, like Active X and MAPI.

    I do know that there has been a lot of griping to MS recently, even among some big institutional adopters of Outlook, about it’s many shortcomings, especially in the cross-platform world. The company that I work for was one of them.

    My question would be, how did Apple get what is apparently a pretty good Outlook client in 10.6? Did they license the tech from MS? No announcement was made…

  3. In 2006 I used MAPI via Python to migrate my address book and calendar from Outlook to OS X’s Mail and iCal apps, and just copied emails over to my IMAP server to migrate the emails themselves. It’s a fairly clunky API. The Outlook object model did not provide access to every characteristic of an email, such as the detailed headers, at least it did not with Outlook 2000, the version I used when migrating.

    Opening PST up does nothing to make Outlook a platform – you always access a platform through well-defined APIs that can stay constant even when the underlying file format changes. It also does not benefit Microsoft, only people who are writing utilities to migrate away from Outlook to something like Evolution or Thunderbird. Mozilla already has Outlook migration support in Thunderbird, however (probably via the official Microsoft APIs), so this is rather late in the game. In all likelihood this effort was part of the settlement between the EU and Microsoft.

  4. Overall this is a good thing. Developing against .PST files can be done today and yes, its a nightmare (via MAPI), but it does work if you put the effort into it. By documenting .PST internals, hopefully better access methods and higher level functionality can be created (open source community, are you listening?!). Google already has a mail extractor for Outlook .PST so I dont think this changes thiings too much from that vantage point.

  5. I would call it a preemptive strike.
    Email clients will be changing in the next few years, WAVE … RAINDROP. Microsoft was never good at developing ideas or a guiding line for development (what on earth is Ray doing these days), so let other people experiment. It’s much cheaper too.
    I can just see some Developers going. MS has an installed base of Xm, Wave Xt, Raindrop Xh. So let’s build my new ueber email client to include MS mail or integrate to run in Outlook …

  6. the crazy thing has always been that you cannot use outlook with free hotmail accounts. instead you have to use gmail or aol mail if you want to use the microsoft email client. i know you can use windows live mail client but that is not as full featured.

    they need to get with the crowd and support POP and IMAP with hotmail.

  7. Anonymous

    MAPI access is proven to be very unstable over the years and it caused many companies developing plug-in systems for Outlook great headaches.

    We in eM Client virtually love this move since it allows us to do fast and seamless migration from Outlook. Even when Outlook is crashed we’ll be able to take .pst from users backup and import it to eM Client (or any other client)

    Outlook would be a great platform if opened few years ago -> now it’s rule will be hopefully over with upcoming thin clients or unified messaging clients like eM (

  8. Perhaps I am missing something, but to access the PST via MAPI or Outlook objects, one must actually have Outlook licensed and installed. This opening of the format allows a server to parse the PST without actually licensing Outlook, in order to edit and update stored information. This creates the ability to improve search indexing, information discovery, backup processes, and information sharing on systems which don’t or can’t install Outlook, from Linux and web servers to potentially portable devices.

    I’ve written some Python which calls the MAPI and OOM interfaces via the Redemption library ( and it was a nightmare. This pst opening is a good first step, in the hopes that simpler ways to access knowledge from emails will be developed.

  9. If you can get IMAP or POP access to Outlook, not too bad migrating email that way.

    This is why using Microsoft products is so aggravating. Everyone else can use standard MBOX mailbox formats which are not only open but work better.