Wcf error - how resolve the error : there was an error generating the XML document?

public bool WriteDataTable(DataTable dt)
        {
            try
            {               
                SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["StrConnection"].ToString());
                SqlCommand cmd = new SqlCommand("INSERT dbo.VPG02(column list) SELECT column list FROM @dt;", connection);
                cmd.CommandType = CommandType.StoredProcedure;
                SqlParameter tvparam = cmd.Parameters.AddWithValue("@dt", dt);
                tvparam.SqlDbType = SqlDbType.Structured;
                cmd.ExecuteNonQuery();
            }
            catch
            {
                return false;
            }
            return true;
        }

MyService.WriteDataTable(dt);

There was an error in serializing body of message InsertRequest: 'There was an error generating the XML document.'.  Please see InnerException for more details.