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Unfortunately because Reckon Accounts Business 2013 desktop edition requires a desktop email client to send emails, users who have upgraded to the Cloud based Outlook 2013 are experiencing compatibility troubles.
Whilst Reckon does not currently support Office Outlook 2013 we expect that Accounts Business 2013/14 is will be compatible with Outlook 2013. In the meantime we do have a workaround that a number of Outlook 2013 users found to be successful:
Note: Under Compatibility mode, ensure the box next to Run this program in compatibility mode for is un-ticked