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I'll show you how to move from Outlook Express to Windows Live Mail on Windows 7 (the easiest moving option), step by annoying step.
I get variations of this question a lot since Microsoft made the decision to remove Outlook Express - or any email program for that matter - from Windows 7.
Unfortunately, Outlook Express is not available for Windows 7.
That means it's time to migrate to a different email program.
In this (lengthy) article, I'll show you how to move from Outlook Express to Windows Live Mail (the easiest moving option), step by annoying step. With lots of pictures.
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I'm going to assume that you're also switching machines. It's OK if you're not; you'll get to skip a few steps, but for the most part this process applies equally whether you're moving from one machine to another, or just upgrading an existing machine to Windows 7.
In Windows XP
Don't worry if you've already upgraded to Windows 7 and XP's no longer around. I'll address that in a moment. Particularly when you're moving machines, though, there are a couple of things you can do before the upgrade to make life just a tad simpler.
In Outlook Express, locate the "message store" folder. Click on the Tools menu, Options... menu item, Maintenance tab, Store Folder... button:

You can actually click-and-drag to select the store folder name therein - just make sure to drag to the far right to get it all, then right click on it and you can select copy:

It'll probably give you something very similar to this:
C:\Documents and Settings\LeoN\Local Settings\
Application Data\Identities\
{99ABF0C2-AAC3-40FD-939D-73857B3D056C}\
Microsoft\Outlook Express
(Though all on one line, and of course some of the specific text will be different.)
Open up Windows Explorer (Windows Key + E is easiest), and paste that into the address bar and press Enter:

This entire folder, including all the files and subfolders within it must be copied to your Windows 7 machine. It really doesn't matter how you do it; you can burn a CD or DVD, copy to a flash drive or removable hard disk, or even copy directly over the network. What matters is that the entire folder is somehow copied to the Windows 7 machine.
Next, your address book.
In Outlook Express, click on the Addresses toolbar button, then in the resulting Address Book Window, click on the File menu, Export menu item, and Address Book (WAB)... sub-menu item:

Enter a file name and save the address book export in some location. (You may need to repeat this once for each identity you use if you use more than one - be sure to select a unique name for each.)
All of these exported address books must now also be copied to your Windows 7 machine.
Finally, you'll need to note, save or record your email account configuration, as there is no automated process to transfer it to your new installation.
In Outlook Express click on the Tools menu, Accounts... menu item, Mail tab. For each account listed there click on the account and then the Properties button.
In the General tab:

Take note of your Name and E-mail address configured.
In the Servers tab:

Take note of all your settings here. If "My server requires authentication" is checked, then click on the Settings... button and note all your settings in the resulting dialog.
On the Advanced tab:

Take note of all your settings in this dialog as well.
If You've Already Left Windows XP
If you no longer have access to Windows XP - presumably because you've upgraded to Windows 7 in place, then you'll need to:
Locate your Outlook Express store on your machine. You may be able to infer its location from the examples above. Another alternative is to search your machine for the file "Folders.dbx" - the folder containing that file is likely the folder you'll need to use below. No need to copy it, simply note its location for use later.
Locate your old Windows Address Book. In Windows XP its in a folder similar to:
C:\Documents and Settings\LeoN\Local Settings\
\LeoN\Application Data\Microsoft\Address Book\LeoN.wab
All on one line, and with your login name instead of mine. If you had multiple identities in Outlook Express there may be more than one. I find it easiest to once again search, this time for "*.wab" to locate all the Windows Address Books. And once again, no need to copy, simply make note of where you found them.
You'll need to remember your account configuration, or get it again from your ISP or email service provider.
Windows 7
Windows 7 does not come with an email program, so you'll need to download and install one.
We'll go get Windows Live Mail, which is similar to Outlook Express, and a free download from Microsoft.
Visit Windows Live's download page:

Download and run the Windows Live installer. (You may have to confirm with Windows 7 UAC.) It'll present you with a list of optional components you can install:

Uncheck everything except Mail. (That is, unless you know you want some of the other components. You can also add them later.)
Click Install. Upon completion of the install (it can take a while), uncheck all the additional options you're offered - we just want mail. (Unless, of course, the options are actually things you want. If you're not sure, uncheck them - you can add them later once you decide.)
It's also up to you if you want to create a Windows Live ID. Given that we're moving your existing email accounts, it's not required that you set up a new one.
Off the Start menu, under All Programs you'll find Windows Live, and within that Windows Live Mail. Click that to launch Windows Live Mail (WLM).
The first time you start WLM it'll launch the "Add an E-mail Account" process. Complete the process with the information that you saved from your Outlook Express account configuration above. Upon successful completion it may immediately download new mail - that's ok. It will also create an Inbox and other folders for your newly configured account.
Coming from Outlook Express, you'll probably be much more comfortable with a traditional menu bar in place. On the right side of the WLM window is an icon, shown below. Click that and then click on Show menu bar:

Now, click on the File menu, Import menu item, Messages... sub menu item. In the resulting dialog box:

Choose Microsoft Outlook Express 6 and click Next.
In the next dialog - "Location of Messages" - click the Browse... button and navigate to the folder that has your Outlook Express messages that we saved or located above. This can once again be on external media, or directly on your machine. Simply locate the folder containing the infamous ".dbx" files. Click Next, make sure "All folders" is selected in the resulting dialog, and click Next again. WLM imports your email, after which you can click Finish.
Your messages have been imported - but where did they go?
It's not obvious, what WLM does is set up a new "Imported Folder" folder within the "Storage Folders" in the program:

All your messages are here. You can now manage them as you see fit, perhaps leaving them there, perhaps dragging and dropping them into other folders - whatever you like.
Last but not least: the Address Book.
In Windows Live Mail, click on Contacts in the lower left:

That brings up the Windows Live Contacts application, into which we'll import the old Windows Address Book.
Click on the File menu, Import menu item, Windows address book (.WAB) sub menu item. It'll then prompt you for the location of your ".wab" file. Navigate to the location containing the .wab file you copied or located earlier and press OK.

That's really all there is to it. Your contacts are imported. You may need to repeat for multiple .wab files if you have them.
Caveats
As complicated as all that may seem, conceptually it's fairly simple: move mail, move address book, copy account settings.
There are a couple of lingering issues.
Windows Live Mail is not Outlook Express. It's similar, but there are differences, and the differences will take a little getting used to. About all I can suggest is that you be patient and embrace change.
In particular, advanced usage of Outlook Express - such as using Identities - may not be preserved. Windows 7 pushes the concept of completely separate Windows user accounts over Identities within Outlook Express.
The good news is that after having set up Windows Live Mail on your Windows 7 machine, it makes migrating to other email programs such as Thunderbird or Outlook that much easier should you decide to switch again later.
Article C4318 - May 19, 2010
Leo, I read your article and feel encouraged however I am concerned there might be system requirements in order to update windows since my computer is so old. I have a desktop with XP for home and outlook 2003. I have no idea what version of explorer we are running. We are trying to put off replacing this dinosaur until after August (bonus check time, yeah!) After reading the above and not being too techie myself I worry that since our computer was built in 2003 that it might not be able to "handle" windows 7. And to clarify, does upgrading to windows 7 upgrade my explorer version? I have no idea what version I have but I do know that various sites we visit recommend updating our browser. We've just been scared to make a leap for fear of crashing this old dinosaur. Is there anything we should first check before switching to windows 7 and transferring our outlook? Thanks so much!
07-Feb-2012
@Tiffany
Posted by: connie at February 6, 2012 5:12 PMHere's another article on Ask Leo! that will answer many of your questions:
Steps to Upgrade Windows XP to Windows 7
I did everything as described, also made sure that the .dbx files are NOT "read only", but the Live Mial just show an empty folder where I stored my OE files, and tells me that there are no mails to import when I try. What am I doing wrong?
Posted by: Kevin in Monaco at April 23, 2012 3:48 AMNice clear instructions but unfortunately it did not work for me. I am trying to import Outlook Express .dbx email message files from a defunct internal hard drive now connected via USB in an external case to a Windows 7 laptop. I can see all the .dbx files but using the import function in Windows Live Mail it won't recognise them as email files. Do you have any other advice/suggestions? Thanks, Mark
Posted by: Mark at April 26, 2012 5:53 AMThanks Leo,
Posted by: Tim Dorse at May 28, 2012 10:06 AMMomentarily I'm going to buy a new HP Laptop (Memorial Day Sale...) with Windows 7. My old desktop is MS XP with Office Professional and Outlook/Outlook Express.
Your article looks like the best way to do the change/transfer.
Sincere Thanks again Leo!
Tim Dorse
{email removed}