ASP.net app crashes - Could not load file or assembly 'Microsoft.Threading.Tasks.Extensions.Desktop'

Question

I want to build a Google BigQuery C# ASP.net application using OAuth2 and the .Net 4.5 framework. I ran these NuGet installs

Install-Package Google.Apis.Bigquery.v2 -Pre
Install-Package Google.Apis.Authentication.OAuth2 -Version 1.2.4696.27634

Install-Package Google.Apis -Pre
Install-Package Google.Apis.Auth -Pre

and I placed the relevant "usings" in code-behind file "default.aspx.cs":

using System;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using Google.Apis.Auth.OAuth2;
using Google.Apis.Services;
using Google.Apis.Bigquery.v2;
using Google.Apis.Bigquery.v2.Data;

namespace BigQueryDemoApp
{
    public partial class _Default : Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            UserCredential credential;
            FileStream stream;

            using (stream = new FileStream(
                    Server.MapPath("~/client_secrets.json"),
                    FileMode.Open, FileAccess.Read)
                )
            {
                GoogleWebAuthorizationBroker.Folder =
                    "Tasks.Auth.Store";
                credential = GoogleWebAuthorizationBroker.
                    AuthorizeAsync(
                    GoogleClientSecrets.Load(stream).Secrets,
                    new[] { BigqueryService.Scope.Bigquery },
                    "user", CancellationToken.None).Result;
            }

            // Initialize the service.
            var Service = new BigqueryService(
                new BaseClientService.Initializer()
                {
                    HttpClientInitializer = credential,
                    ApplicationName = "BigQueryDemo"
                }
            );
        }
    }
}

I set this specific page as the project start page. I picked "Installed application" when I built the Client ID file at the Google console

APIS & auth -> Credentials -> CREATE NEW CLIENT ID

and I made sure I added this file (client_secrets.json) with the solution explorer in VS2013. In the code-behind, I made sure that I correctly mapped to the client_secrets file with Server.MapPath. For the credential machinery, I used this code

<https://code.google.com/p/google-api-dotnet-client/wiki/OAuth2>

as the starting point. When I run the app, it returns a browser error page that starts with

Could not load file or assembly 'Microsoft.Threading.Tasks.Extensions.Desktop, Version=1.0.16.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.

and crashes at the "credential =" line. I tried to add in some images of the actual ASP.net crashed browser page showing the Assembly Load Trace / Stack Trace / etc. but it looks like I don't have the account rights for this. When I set a breakpoint at the "credential =" line and then run the app through

DEBUG -> Start Debugging

in VS2013, the page stops at the "credential =" line and a file picker opens, looking for file

"GoogleClientSecrets.cs"

from directory

"c:\code\google.com\google-api-dotnet-client\default\Tools\Google.Apis.Release\bin\Debug\output\default\Src\GoogleApis.Auth\OAuth2\GoogleClientSecrets.cs"

which is nowhere on the drive. Using the Assembly Load Trace in the generated ASP.net error page, I tried digging around through the suggested configuration files but nothing worked. More generally, I tried looking for this issue in StackOverflow and while I did find some mention of it, none of that material helped.

Answer 1

Because the error is based on the fact that the latest version of Microsoft.Bcl.Async doesn't work in .NET 4.5, you can try to do the following:

Open your Package Manager Console, and run the following commands:
1) Uninstall-Package Microsoft.Bcl.Async -Force
2) Install-Package Microsoft.Bcl.Async -Version 1.0.16

It works in a sample I'm currently writing. Please let me know if it works for you.

UPDATE (March 21st): You can update the package (new version 1.0.166-beta is available - https://www.nuget.org/packages/Microsoft.Bcl.Async/1.0.166-beta).
I tested it on VS2013 with .NET 4.5 framework and it works.