ExecuteNonQuery: Connection property has not been initialized.
I GET THE ABOVE ERROR WHEN I EXECUTE THE PAGE
 
String strConnString = ConfigurationManager.ConnectionStrings["EMPLOYEEConnectionString2"].ConnectionString;
//SqlConnection con = new SqlConnection();
protected void btnSave_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(strConnString);
 con.Open();
 // con.ConnectionString = new SqlConnection(strConnString);
 SqlCommand cmd = new SqlCommand();
 cmd.CommandType = CommandType.StoredProcedure;
 cmd.CommandText = "JOINMAX";
 cmd.Parameters.Add("@NAME", SqlDbType.VarChar).Value = txtName.Text.Trim();
 cmd.Parameters.Add("@EMAIL", SqlDbType.VarChar).Value = txtEMAIL.Text.Trim();
 cmd.Parameters.Add("@PHONENO", SqlDbType.VarChar).Value = txtPHONE.Text.Trim();
 cmd.Parameters.Add("@ERROR", SqlDbType.Char, 500);
 cmd.Parameters["@ERROR"].Direction = ParameterDirection.Output;
 cmd.ExecuteNonQuery();
string message = (string)cmd.Parameters["@ERROR"].Value;
con.Close();
}
 }
}