After entering the following below contact details I get a duplicated one in my address book in Outlook.com account. Maybe it's an Outlook issue or an iOS issue. Here is what my contact format looks like from the native Phone contact app. First Name: Company Inc Last Name: left blank Company Name: left blank Home/fax: number of Company Inc Email: CompanyInc@abc.com Then when Done, it synchronizes to my Outlook mail client Address Book and shows as duplicate. Now I managed to delete the other line or entry and now is fine. Is this an iOS or Outlook issue?