Yesterday I stumbled into an issue. My custom task outcome of SPD 2013 workflow stopped to function properly. It set to default value regardless of the Task Outcome I set programmaticaly in my custom ASP.NET task form.
My task settings looked as follows:
But when I pressed “Reject” or “Approve” button in my form, my ApprovalOutcome variable set to “Approved”. When I changed Default Outcome to “Rejected” this variable set to “Rejected” regardless of pressed button.