New Outlook profile: "The profile name you entered already exists"
When troubleshooting users’ Outlook problems, administrators often create several Outlook profiles so they can login to Outlook as the user.
When you create and delete a profile for the same user several times, you might end up by getting an error message saying “The profile name you entered already exists. Enter a different profile name.” even though you can’t see the profile in the Control Panel.
This is caused by Outlook not completely removing the profile information from the system, more specifically from the Registry. To fix this, navigate to
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles
And delete the key with the name matching the user that you are trying to create a profile for!