System.InvalidOperationException: Instance '[private Queue path]' does not exist in the specified Category

Question

I am using following code to get message Queue count time to time from this method is calling on every 15s

public JObject GetQueueItemsCount()
{

               JObject returnObject = new JObject();
                int queueCount = 0;
                var queueName = @"" + ConfigurationManager.AppSettings["QueueName"];
                try
                {
                    MessageQueue messageQueue = new MessageQueue(queueName);
                    if (MessageQueue.Exists(queueName))
                    {

                        var queueCounter = new PerformanceCounter("MSMQ Queue", "Messages in Queue", queueName, @"" + ConfigurationManager.AppSettings["MachineName"]);
                        queueCount = (int)queueCounter.NextValue();
                    }


                }
                catch (Exception ex)
                {

                    throw ex;
                }

                finally {
                    returnObject.Add("queueCount", queueCount);
                }
                return returnObject;
            }

The problem is that following Exception is sometimes thrown:and this exception throws when the message queue count become 0 basically for a newly created queue

System.InvalidOperationException: Instance 'xxxxx\private$\xxx_queue' does not exist in the specified Category.
  at xxxxx.BusinessObjects.ControllerRepositories.xxxxRepository.GetQueueItemsCount()
  at lambda_method(Closure , Object , Object[] )
  at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters)
  at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)
------

Answer 1

I believe this is because the Performance Counter either doesn't exist yet (for a new queue that has never had any messages), or was removed. Since you're instantiating the MessageQueue object anyway, a more reliable way to get the count may be to call messageQueue.GetAllMessages().Length. As long as you don't have the Body property enabled in your MessageQueuePropertyFilter, it shouldn't be extremely expensive.