C# DateTimePicker problem

Question

Hey, I'm trying to use some basic input validation for two dateTimePicker controls in an application I'm building.

I'm trying to set it so that the issueDatePicker's value or date & time must be smaller (less than) that of the dueDatePicker's value or date & time.

I'm using this code which seems correct but just isn't working..

                if (issueDatePicker.Value >= dueDatePicker.Value)

                {

                    MessageBox.Show("The due date must be greater than the issue date", "Input Error");

                }

                else

                {

                    issueDate = issueDatePicker.Value;

                    dueDate = dueDatePicker.Value;

                    dateCorrect = true;

                }

The above code is within a button click event.

Any help is appreciated.