How do I disable the "Delete" button under Task/Time tab in the CSR? (4283994)

How do I disable the "Delete" button under Task/Time tab in the CSR?

There are two security rights in Stat that can disable the Delete button under Task/Time tab. They are under the "CSR Tabs" rights group and are: 

Task/Time Tab - Delete System Added

Task/Time Tab - Delete User Added 

The first security right disables the delete button for the tasks that are generated automatically when the CSR is created and the second disables the delete button for the tasks that are manually generated by users when they mouse click on "New" tab under Task/Time tab.