ExMerge: Goodbye to an old friend

One of the most specialised tools that I regularly use and absolutely love is the Microsoft Exchange Server Mailbox Merge Wizard. (ExMerge) Lately I find myself pondering about the future of my old friend, which has been my partner in crime in the last past years.

What ExMerge does

The Microsoft Exchange Server Mailbox Merge Wizard is an utility designed to close the gap between the Microsoft Information Stores on one end and Public Folders (PST files) on the other end. I use it in a variety of ways:

  • I use it to migrate naughty users that store e-mail items, like their messages and their calendars in PST files because they don’t know how to operate Microsoft Outlook, because they think it’s safer to do that or because they’re just blatantly stupid. I don’t even care anymore: when I come across a PST file I’ll make it part of Exchange again.
  • I use it to migrate mailboxes between Microsoft Exchange servers that aren’t supposed to know each other intimately, for instance that odd little department that decided to organize their own IT instead of relying on the global company and don’t want Big Mama to find out.
  • I use it to eliminate unwanted data from Microsoft Information Stores but still complying with regulatory issues. For instance when they fired that odd CEO but still want to keep his e-mail on a CD-R in the vault in case he decides to sue. I also used it to extract the mailbox of a user from an Information Store, mounted inside a Restore Group once. Big fun!

PST’s are evil

If you’re using one at home because you don’t have an Exchange server I guess you have a valid excuse to own a Personal Folder file, but everyone else that thinks using a Personal Folder file in a corporate environment should be hospitalised and treated with shock therapy.
I don’t know how to describe how much I hate Personal Folder files, but I can describe why I hate them:

  • They’re slow, because you store them on your local hard drive which is at best a Serial ATA disk connected to an ‘el cheapo’ controller chip. I think you might get better performance when it’s stored on a RAID volume made up of 15k SCSI disk in our dedicated Exchange server.
  • You can secure them using a password
    And then of course you can ask Microsoft Outlook to automatically supply the password to open the PST file and forget all about it.
  • Single Instance Storage… huh?
    One of the best features of Microsoft Information Stores is they use Single Instance Storage so mail only gets stored inside the database once. Imagine one of your colleagues e-mailing a 2MB photo to 1000 other colleagues and everyone stores that message inside a PST file on your fileserver. Instead of a 2MB increase of your Information Store you end up with a 2GB increase on your fileserver.
  • Prone to error
    When you use PST files that are compatible with Microsoft Outlook 97, Microsoft Outlook 2000 and Microsoft Outlook 2002 (also known as Microsoft Outlook XP) you’re stuck with a 2GB barrier. Your file will not grow any bigger without littering itself. If you let this happen you will need a technician to troubleshoot your mailbox and you will lose data.
  • You can’t share them with colleagues and you can’t access them with Outlook Web Access because the PST file is not a part of Microsoft Exchange anymore. Instead it resides on the hard disk of your computer which is switched off during the night. Making it available offline on your laptop isn’t a good idea either: you’ll find yourself surrounded with nice errors.
  • You don’t get back-ups automatically because your silly systems administrator only has to make back-ups of the files on the fileserver and no matter how hard you try your boss isn’t able to persuade him into backing up your workstation as well.

That’s why ExMerge is my hero. It eliminated many PST files, it created happy customers, it gave me a reason to make jokes of colleagues with PST files and I guess it actually gave a significant boost to my career. (if that’s what you call it…)

So why ponder?

Lately I’m running into problems that my little friend can’t solve and I’m reading disturbing news on the Microsoft website and on the website of the Microsoft Exchange team.

ExMerge can’t handle Unicode PST files.

The 2GB limit on PST files got eliminated by Microsoft Office Outlook 2003. This version of Microsoft Outlook introduced a new file format which isn’t backward compatible with previous versions of Microsoft Outlook and got known as the ‘Unicode PST’. Unfortunately there is no way of importing an Unicode PST file into a Microsoft Exchange Information Store. You will need to use the import feature of Microsoft Outlook for this.
Unfortunately it also means that you won’t be able to export a 2GB+ mailbox from within Microsoft Exchange Server to a PST file with ExMerge at once. You will need to use the filter options to export to PST files that are less than 2GB in size.

ExMerge is getting ‘de-emphasized’.

Microsoft Exchange Server 2007 will not ship with an updated version of ExMerge.


Microsoft Exchange Server Mailbox Merge Wizard (ExMerge)
The Exchange Management Shell Export-Mailbox cmdlet or the Move Mailbox wizard can be used to perform the necessary mailbox tasks.

Well, that’s a clear message: Just use the Move Mailbox Wizard or go script something.

The Move Mailbox Wizard

The first thing I did was firing up the new Exchange Management Console on my Microsoft Exchange Server 2007 Beta 2 box but I pretty soon came to the conclusion that the Move Mailbox wizard doesn’t contain an option called ‘Move to PST’ or something similar. It seems to me the functionality of the Move Mailbox Wizard is unaffected between Microsoft Exchange Server 2003 and Microsoft Exchange Server 2007 Beta 2. I don’t know why so many people on so many websites tell people to use the wizard while it doesn’t do the job described. (I guess background checking, information validation and field experience aren’t considered key competences for forum posters and bloggers anymore)

Scripting it is?

I fired up the ‘Exchange Management Shell’ shortcut in my start menu and began typing some commands. One of the first things I did was ‘help export-mailbox’ and fiddle around a bit with this nice command. This pretty soon seemed another dead end street, because this command doesn’t allow exporting mailboxes to PST files. It only allows to export towards another folder in another mailbox.



Not only ExMerge is getting de-emphasized, the functionality of my little friend seems to be heading the same way. In Microsoft Exchange Server 2007 Beta 2 there doesn’t seem to be a way to ‘export to’ or ‘impost from’ PST files. I know PST files are bad, but sometimes they’re pretty handy.

Do NOT listen to people telling you you can work with PST files in Microsoft Exchange Server 2007 Beta 2.  It can NOT be done with the ‘Move Mailbox Wizard’ or the ‘Export Mailbox CMDlet’. You will need to use Microsoft Outlook for this. Let’s hope the Microsoft Exchange team finds a solution for this or someone else writes one.

I guess I’m going to eliminate some more PST files with ExMerge tomorrow while I still can. [:'(]

More reading

Download ExMerge here
Discontinued Features and De-emphasized Functionality in Microsoft Exchange Server 2007
The Export Mailbox CMDLet


Update April 2007

Ricardo Rosales Guerrero made a blogpost on the Microsoft Exchange Team blog explaining the new and improved Import-Mailbox CMDLet in Exchange Server 2007 ServicePack 1… and it allows for Unicode PST files too! The Exchange team really provided a suitable tool with functionality that surpasses Exmerge.

A beta of this ServicePack is available, if you'd really need this functionality.

One Response to ExMerge: Goodbye to an old friend


    Yesterday I spoke a little with Jim McBee on this and he told me he heared rumours (can't get any more vague than that, can it?) about the Microsoft Exchange team actually programming PST export (and import) capabilities into the CMDLet.

    Let's hope this is going somewhere… [^o)]

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