All the .dbx files for each user should be in a single folder.
If you have 4 users, there will be 4 folders with each users .dbx files.
Depending on the version of Windows, and IE, the default folders are in a common location.
The only issue comes up when a user manually selects a different folder location.
You can find the folder location by clicking on
Tools
Options
Maintenance
Store Folder
This will display the store folder path for each user.
In Windows XP, the default path is:
C:\Documents and Settings\{user name}\Application Data\Microsoft\Outlook Express
In W98 with OE 5.5 or 6, the path is along the lines of
C:\Windows\Application Data\{string}Microsoft\Outlook Express
(on my XP box at the moment, so this is an approximation)
For older versions of OE, the path is
C:\Program Files\Outlook Express\{user}\
There are also programs that are designed to specifically back up OE mail files.
Chas