Origninal Article: http://smallbusiness.chron.com/renaming-outlook-profile-70020.html
Your Microsoft Outlook profile is what the application uses to remember your email as well as the custom settings that you create. Initially, your Outlook profile may be named something pragmatic, like the first initial of your first name followed by your last name. However, if you create multiple profiles, it becomes more helpful to name the profiles something that points to their uses (such as "Office Email" or "Home Email.") You can't change the Outlook profile name in the application's settings, but you can change it in the Windows registry.
- Press "Windows-R" on your keyboard to launch the "Run" command program.
- Type "regedit.exe," and then press "Enter." The Windows Registry editor will open.
- Click the downward facing triangle next to "HKEY_CURRENT_USER" followed by "Software," "Microsoft," "Windows NT," "CurrentVersion" and "Windows Messaging Subsystem." Click "Profiles" once to highlight it.
- Right-click the "DefaultProfile" key in the right pane of the Registry window, and then select "Modify."
- Rename the key what you would like the Outlook profile to be named.
- Click the downward facing triangle next to the "Profiles" link in the left pane of the Registry window. The name of the profile that you wish to rename should appear below. Right-click this profile name, and then select "Rename."
- Rename the profile the same name you used to rename the DefaultKey in a previous step. Exit Windows Registry, and then open Microsoft Outlook to see that the profile name has changed. If the profile name hasn't changed, exit Microsoft Outlook and reopen it. If it still hasn't changed, make sure that you've named the DefaultKey and the profile name exactly the same.