fix for issue

Src/Newtonsoft.Json/Utilities/ConvertUtils.cs

@@ -30,6 +30,7 @@ using System.ComponentModel;
 #if !(NET20 || NET35 || PORTABLE40 || PORTABLE)
 using System.Numerics;
 #endif
+using System.Text;
 using Newtonsoft.Json.Serialization;
 using System.Reflection;
 #if NET20
@@ -395,6 +396,8 @@ namespace Newtonsoft.Json.Utilities
                     return new Uri((string)initialValue, UriKind.RelativeOrAbsolute);
                 if (targetType == typeof(TimeSpan))
                     return ParseTimeSpan((string)initialValue);
+                if (targetType == typeof (byte[]))
+                    return ParseBytes((string) initialValue);
                 if (typeof(Type).IsAssignableFrom(targetType))
                     return Type.GetType((string)initialValue, true);
             }
@@ -438,6 +441,12 @@ namespace Newtonsoft.Json.Utilities
 
             throw new InvalidOperationException("Can not convert from {0} to {1}.".FormatWith(CultureInfo.InvariantCulture, initialType, targetType));
         }
+
+        private static object ParseBytes(string initialValue)
+        {
+            return System.Convert.FromBase64String(initialValue);
+        }
+
         #endregion
 
         #region TryConvert