Try leaving it blank or see “What Domain Name Do I Enter? Many corporate networks have different Exchange server names inside and outside the firewall.
Synchronizing your Outlook (cached) address book with the Global Address book may fix these discrepancies.In today´s business environment, many professionals must use several email accounts.With such a diversity of services to choose from, including calendars, contacts, notes or tasks, it can be hard to navigate more than one account.You can use the stock calendar, S-Planner on Samsung phones, HTC Calendar on HTC, or Google Calendar's official app to test this.If they work and Digi Cal don't - please send us an email with the details. Check the sync status of the phone and account, they must be all enabled to allow syncing.
This issue has been reported in organizations with Microsoft Exchange, Outlook (2003, 2007, 2010 or 2013), Apple i Phones/i Pads/i Pods, Active Sync devices, Apple Macs running Entourage or Outlook 2011, and RIM Blackberries.