Outlook Express has the ability to have multiple users who can have their own settings as to appearance and e-mail and news accounts. This information is stored in two locations. For the settings, this information is stored in the registry. For the messages, they are stored on the local hard drive. Outlook Express is not really set up for network use as the message stores are fragile and can cause corruption which can lead to lost messages so recommending you try to do this is not advisable.
The message stores (.dbx files) are located on the local hard drive and is usually stored in the Windows\Application Data\Identities folder for Windows 9x and Me. For Windows NT, 2000 and XP, they are generally in the User's folder in the Documents and Settings folder. . Again, each Identity will have it's own store folder to separate users' messages. This information can be found in the Tools | Options | Maintenance tab sheet by pressing the Store Folders button.
The settings are stored in the HKEY_CURRENT_USER\Identities key. Each Identity set up will have its own Global Unique IDentifier {GUID} which is different from user to user and from computer to computer. It is a long row of numbers and letters enclosed in braces { }, hence the reason you see {GUID} used as such in newsgroups. This is actually a hexadecimal number (base 16 - numbers 0 - 9 and letters A - F).
Since each Identity is given a {GUID} and username., finding which Identity's {GUID} belongs to which Identity is pretty easy. A string in each {GUID} key has a string of Username and it's value is the friendly name of the Identity.
To access this information, you should have some knowledge of the way the registry and its tool, Regedit, work. Microsoft has a web site for further information on Regedit located at Microsoft Product Support Services (formerly the Knowledge Base) http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q293130
Ok, enough with the hokey poky bologna and let's look at what is where in all this stuff.
Press the START button.
Select Run...
Type in the following, and press ENTER afterwards.
Regedit
Up pops the registry editor and we begin to look around.
Press the + sign next to HKEY_CURRENT_USER in the left
window pane.
Press the + sign next to Identities in the left
window pane.
If you only have one Identity, the Main Identity, when you press the + sign next to Identities, you will only see one {GUID} listed. If you have more than one, you will see several {GUID}, depending upon how many Identities are set.
Now, in the right window pane, you will see several items:
Directory Name
Identity Ordinal
User ID
User Name
The Directory Name is the folder location on your hard drive. It's encoded so that's why it looks weird.
The Identity Ordinal, is the number of the Identity. If you have one Identity, it should show 1.
The User ID is the {GUID}.
The User Name is the one we're looking for, it shows the name that is given to the Identity. That helps you identify which {GUID} belongs to which Identity if you need to make changes, import or export registry entries.