We are using Umbraco v7.5.7, Archetype v1.13.0, Newtonsoft v6.0.0 and RJPMultiUrlPicker v1.3.1 and are experiencing the following issue.

We have a class as follows:

public class LinkItem : ArchetypeFieldsetModel
{
    public int? Id { get; set; }
    public string Name { get; set; }
    public string Target { get; set; }
    public LinkType Type { get; set; }
    public string Url { get; set; }
}

and have created a custom TypeConverter that has the following method:

    public override object ConvertFrom(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value)
    {
        var result = JsonConvert.DeserializeObject<List<LinkItem>>(value.ToString());
        return result;
    }

when this runs we are getting the following error message:

[ArgumentException: Could not cast or convert from System.String to System.Guid.]
   Newtonsoft.Json.Utilities.ConvertUtils.EnsureTypeAssignable(Object value, Type initialType, Type targetType) +225
   Newtonsoft.Json.Utilities.ConvertUtils.ConvertOrCast(Object initialValue, CultureInfo culture, Type targetType) +123
   Newtonsoft.Json.Serialization.JsonSerializerInternalReader.EnsureType(JsonReader reader, Object value, CultureInfo culture, JsonContract contract, Type targetType) +348

[JsonSerializationException: Error converting value "1098" to type 'System.Guid'. Path '[0].id', line 3, position 17.]

which is confusing as the object it is trying to be converted to does not have a Guid declared. The source JSON data looks as follows:

[\r\n  {\r\n    \"id\": \"1098\",\r\n    \"name\": \"Contact us\",\r\n    \"url\": \"/contact-us/\",\r\n    \"icon\": \"icon-article\"\r\n  }\r\n]

This was working in an earlier version of Umbraco (v7.1.9) and Archetype (v1.7.5) with the same version of RJPMultiUrlPicker and Newtonsoft but now no longer works as above.

Any ideas???