Failed to save mailbox

Inherited an issues with an existing admin email address in virtualmin but can not see the admin user. Any suggestions on how to locate this admin user. The error I receive is:

Failed to save mailbox : A mailbox or mail alias with the same name and domain already exists

So if you go into “Edit Mail and FTP Users” or “Edit Email Aliases”, you don’t see the account/alias you’re trying to add?

Assuming you don’t see it there – is it a brand new email account you’re trying to add, or just an alias? If it’s an email account, do you see the account in question in /etc/passwd?