There are several ways to do this including some software applications that will do it for you but the manual method is easy enough.
1. locate your OE store folder which contains the mbx files and is usually at a location like
C:\WINDOWS\Application Data\Identities\{long_number-xxxx-xxxx-xxxx-xxxxxxxxx}\Microsoft\Outlook Express
for Windows 9x or
C:\documents and settings\username\Application Data\Identities\{long_number-xxxx-xxxx-xxxx-xxxxxxxxx}\Microsoft\Outlook Express
for Windows 2000 or XP
2. copy that folder to your new computer
3. Open Outlook express on the new PC and set up your email ccount in it (or it won't let you do the next step).
4. In Outlook Express Click on the File menu->Import->Messages
which will open a dialog box asking what you want to Import from - choose Outlook Express X depending on which version it is and then you can either Browse (OE4) or Import from Outlook Express Store Directory (OE5-6) - either of which you point at your copied data.
The rest is self explanatory
Good Luck
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