When you use Microsoft Outlook 2013 to connect to an Exchange ActiveSync (EAS) account, you cannot create Contact Groups. Additionally, the New Contact Group button is unavailable.
Contact Groups are not supported in Exchange ActiveSync (EAS). Outlook 2013 uses EAS to connect to @outlook.com, @hotmail.com, @live.com, and @msn.com email accounts.
If you are upgrading from Outlook 2007 or Outlook 2010, you can export your Contacts and Contact Groups to an Outlook Data (.pst) file, and then import them to a new .pst file in Outlook 2013. For more information about importing Contact Groups in Outlook 2013, view the following Microsoft Office website: