Azure Function QueueTriggerCSharp sample

client-sample.cs

using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Auth;
using Microsoft.WindowsAzure.Storage.Queue;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BulkQueue
{
    class Program
    {
        static readonly string Account = "<storage account name>";
        static readonly string Key = "<storage account key>";
        static readonly string QueueName = "samplequeue";
        static void Main(string[] args)
        {
            var credential = new StorageCredentials(Account, Key);

            var tasks = Enumerable.Range(1, 300)
                .Select(i =>
                {
                    return Task.Run(() =>
                    {
                        var account = new CloudStorageAccount(credential, true);
                        var client = account.CreateCloudQueueClient();
                        var queue = client.GetQueueReference(QueueName);

                        var content = $"HelloWorld_{i}";
                        var message = new CloudQueueMessage(content);
                        queue.AddMessage(message);
                        Console.WriteLine(i);
                    });
                });

            Task.WaitAll(tasks.ToArray());

            Console.WriteLine("Hit any key.");
            Console.ReadKey();

        }
    }
}

Exception

...at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.Azure.WebJobs.Host.Blobs.Bindings.WatchableCloudBlobStream.<CommitAsyncCore>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.Azure.WebJobs.Host.Blobs.Bindings.OutStringArgumentBindingProvider.StringArgumentBinding.StringValueBinder.<SetValueAsync>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<ExecuteWithWatchersAsync>d__33.MoveNext()
   --- End of inner exception stack trace ---
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<ExecuteWithWatchersAsync>d__33.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<ExecuteWithLoggingAsync>d__2e.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<ExecuteWithLoggingAsync>d__15.MoveNext()
   --- End of inner exception stack trace ---

function.json

{
  "bindings": [
    {
      "name": "myQueueItem",
      "type": "queueTrigger",
      "direction": "in",
      "queueName": "samplequeue",
      "connection": "buchifunctions_STORAGE"
    },
    {
      "type": "blob",
      "name": "outputBlob",
      "path": "outcontainer/%rand-int%{queueTrigger}.txt",
      "connection": "buchifunctions_STORAGE",
      "direction": "out"
    }
  ],
  "disabled": false
}

QueueTriggerCSharp1.csx

using System;

public static void Run(string myQueueItem, out string outputBlob, TraceWriter log)
{
    outputBlob = myQueueItem;
}

I am unable to repro this issue. @buchizo - Can you try it with latest runtime and let us know if you still see this error?