You have deployed SharePoint 2013 and the MySite functionality has been deployed. When you visit your mysite and switch to the My Tasks screen you will see the below error message.
"Sorry, we're having trouble refreshing your tasks. Contact your administrator if you continue to have problems"
You will need to enable the Work Management Service App.
From your SharePoint Central Administration, under the Applications and Manage Service Applications, create a new Service Application for Work Management Service Application.
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