C# WebClient

I'm trying to send POST data with C# WebClient to a PHP file on my website, then get the http response.


                            WebClient client = new WebClient();
                            byte[] response = client.UploadValues
                            (
                                "http://blackoutgame.net/database/validate.php",
                                new NameValueCollection() { { "username", "test" }, { "password", "test" }, { "ingame", "True" } }
                            );

However, it keeps throwing a (500) Internal Server Error.

The only thing I could think to do was modify the file permissions in my cPanel, which I did, but to no avail.

Wat do?

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