I'm running Windows 10 IoT Core on my Raspberry Pi 2 , and I need to make a call to my Web API using a C# client. Here's my code for it: 
private const string route = "/api/Print";
public bool Update(string header, string tc)
{
    bool success = false;
    using (var client = new HttpClient())
    {
        client.BaseAddress = new Uri("my uri");
        client.DefaultRequestHeaders.Accept.Clear();
        client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
        var print = new Print { CompanyRef = new Guid(), Header = header, TC = tc };
        var response = client.PutAsJsonAsync(route, print);
    }
    success = true;
    return success;
}
public sealed class Print
{
    public string Header { get; set; }
    public string TC { get; set; }
    public System.Guid CompanyRef { get; set; }
}
And here's how I make the call to it:
Update(" header", " string tc");
 
While it works great in my C# Desktop App, it just won't work on the Pi. Although, it works fine when I call a Get from the Web API server. Please Help!