Web api Data Annotations cause 500 server error when passed - asp.net-web-api

Question

I am creating a web api project and want to add validation to my model, so I added a DataAnnotation attribute.
I then tested the project by trying to pass my object from a separate mvc project. I recieved a 500 server error.
Removing the DataAnnotation allows me to pass the object successfully. Why?
I have looked at a couple of tutorials such as this and this, they show how to handle validation errors, but this has not helped.
UPDATE
Removing the data annotation from MyProperty in Class1, solution B (but leaving it on the class in solution A) means values can be passed successfully! Is this a problem with deserilazing the object? If so how do I solve it?
B = My web service reciving the object
A = My mvc project sending the object
my code to send the resquest
public class Class1
{
[Required(ErrorMessage = "MyProperty value is required")]//remove this line to make it work
public int MyProperty { get; set; }
public Class2 MyOtherProperty { get; set; }
}
public class Class2
{
public string SomeProperty { get; set; }
}
async Task<string> Test2()
{
var form = new Class1();
form.MyProperty = 123;
form.Class2 = new Class2();
using (HttpClient client = new HttpClient())
{
client.BaseAddress = new Uri("http://localhost:58814/api/");
var post = await client.PostAsJsonAsync<Class1>("Values", form);
var putt = await client.PutAsJsonAsync<Class1>("Values", form);
}
return "";
}
my code to recieve the request (the breakpoint applied is not being hit)
// POST api/values
public void Post([FromBody]Class1 value)
{
}
// PUT api/values/5
public void Put([FromBody]Class1 value)
{
}

Answer 1

I have resolve the issue thanks to the advice from this link - Scott Hanselman's blog
My sending project and receiving project had identical classes (including data annotations). Removing the annotations from the class in the receiving project resolved the binding issue but I still needed validation on the properties. Also changing the annotation from required to Range also resolved the binding issue (I only mention these as they were some steps I took to try and debug).
The final solution for me was to change this
public class Network
{
[Required(ErrorMessage = "NetworkID is required")]
public int NetworkID { get; set; }
}
to this
[DataContract]
public class Network
{
[DataMember(IsRequired = true)]
public int NetworkID { get; set; }
}