The specified value does not conform to the required format yyyy-MM-dd

The issue could be from the type="date". That was my situation anyway. Worked once it was changed to type="text". If the interface is built with an MVC wrapper, you need to replace or set the html attribute accordingly.

The specifications for the HTML5 date picker state that the date must be in the format yyyy-MM-dd (ISO format). This means that you DisplayFormatAttribute must be

[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
public string MyDate { get; set; }

Alternatively you can manually add the format using

@Html.TextBoxFor(m => m.MyDate, "{0:yyyy-MM-dd}", new { @type = "date"  })

The later option allows you to keep the DataFormatString = "{0:dd/MM/yyyy}") for usage in @Html.DisplayFor()