Could not load file or assembly 'DotNetOpenAuth.Core

I get the following error when I start my asp net mvc 4 application:

Could not load file or assembly 'DotNetOpenAuth.Core, Version=4.0.0.0, 
Culture=neutral, PublicKeyToken=2780ccd10d57b246' or one of its dependencies. 
The system cannot find the file specified

This is the error log

Assembly manager loaded from:  C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
Running under executable  C:\Windows\SysWOW64\inetsrv\w3wp.exe
--- A detailed error log follows. 

=== Pre-bind state information ===
LOG: User = notebook\Guilherme
LOG: DisplayName = DotNetOpenAuth.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=2780ccd10d57b246
 (Fully-specified)
LOG: Appbase = file:///C:/Users/Guilherme/Documents/Visual Studio 2012/Projects/Gedi/Gedi/
LOG: Initial PrivatePath = C:\Users\Guilherme\Documents\Visual Studio 2012\Projects\Gedi\Gedi\bin
Calling assembly : Microsoft.Web.WebPages.OAuth, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35.
===
LOG: This bind starts in default load context.
LOG: Using application configuration file: C:\Users\Guilherme\Documents\Visual Studio 2012\Projects\Gedi\Gedi\web.config
LOG: Using host configuration file: C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet.config
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Post-policy reference: DotNetOpenAuth.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=2780ccd10d57b246
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/2635bb56/154c3fbb/DotNetOpenAuth.Core.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/2635bb56/154c3fbb/DotNetOpenAuth.Core/DotNetOpenAuth.Core.DLL.
LOG: Attempting download of new URL file:///C:/Users/Guilherme/Documents/Visual Studio 2012/Projects/Gedi/Gedi/bin/DotNetOpenAuth.Core.DLL.
LOG: Attempting download of new URL file:///C:/Users/Guilherme/Documents/Visual Studio 2012/Projects/Gedi/Gedi/bin/DotNetOpenAuth.Core/DotNetOpenAuth.Core.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/2635bb56/154c3fbb/DotNetOpenAuth.Core.EXE.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/2635bb56/154c3fbb/DotNetOpenAuth.Core/DotNetOpenAuth.Core.EXE.
LOG: Attempting download of new URL file:///C:/Users/Guilherme/Documents/Visual Studio 2012/Projects/Gedi/Gedi/bin/DotNetOpenAuth.Core.EXE.
LOG: Attempting download of new URL file:///C:/Users/Guilherme/Documents/Visual Studio 2012/Projects/Gedi/Gedi/bin/DotNetOpenAuth.Core/DotNetOpenAuth.Core.EXE.

I have already remove all references from DotNetOpenAuth with packager manager. Also I checked by my self references for every Auth assembly I had in my project and there is none.

This is my packages.config

<packages>
  <package id="AutoMapper" version="2.2.0" targetFramework="net45" />
  <package id="EntityFramework" version="5.0.0" targetFramework="net45" />
  <package id="jQuery" version="1.7.1.1" targetFramework="net45" />
  <package id="jQuery.UI.Combined" version="1.8.20.1" targetFramework="net45" />
  <package id="jQuery.Validation" version="1.9.0.1" targetFramework="net45" />
  <package id="knockoutjs" version="2.1.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.Mvc" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.Razor" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.Web.Optimization" version="1.0.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.Client" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.Core" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.WebHost" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebPages" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebPages.Data" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebPages.WebData" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.jQuery.Unobtrusive.Ajax" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.jQuery.Unobtrusive.Validation" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.Net.Http" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.Web.Infrastructure" version="1.0.0.0" targetFramework="net45" />
  <package id="Modernizr" version="2.5.3" targetFramework="net45" />
  <package id="Newtonsoft.Json" version="4.5.11" targetFramework="net45" />
  <package id="Repository" version="1.0.2.12" targetFramework="net45" />
  <package id="RestSharp" version="103.4" targetFramework="net45" />
  <package id="WebGrease" version="1.1.0" targetFramework="net45" />
</packages>

Thanks

If you don't want use OAuth, remove references: both the WebPages OAuth DLL (I think it's Microsoft.Web.WebPages.OAuth.dll ¹) and DotNetOpenAuth DLLs.

---

¹: You can find the filename in Calling assembly. So, removing all calling assembly of DotNetOpenAuth.Core should work for you. This approach should work for other unused missing references.

I had similar problem. It was really strange as the project was running OK a day before.

Removing obj and bin folders from the project folder, cleaning the solution and rebuilding it worked.

Hope that helps.

I've seen this happen when deploying an MVC application as bin deploy. When you right-click on a project and select Add deployable dependencies VS will add the references to Oauth if you check the box next to ASP .NET Webpages with Razor syntax.

To fix this, delete the _bin_deployableAssemblies folder, and your application's bin folder and then clean and rebuild your application and it will work again.

In my case the MVC4 application was running fine in the VS2012 debugger, but I was getting the "Could not load file or assembly 'DotNetOpenAuth.Core'" error when I publish the application on the server.

Checking the "Delete all existing files prior to publish" checkbox on the settings tab of Publish Web window solved the issue.

I solved the problem by installing the package using Nuget

Install-Package Microsoft.AspNet.WebPages.OAuth

Just select "Remove additional files at destination" on publish settings. This works for me

By installing the following two packages I resolved this problem on VS2012 Professional Update 4 RC:

1. Open the Package Manager Console from the Menu:

   Tools| Library Package Manage | Package Manager Console

2. Install-Package DotNetOpenAuth.AspNet

3. Install-Package Microsoft.AspNet.WebHelpers

Hope this helps for you!!!

Try doing a global solution search (ctrl+shift+f if you haven't changed it) for the value '2780ccd10d57b246'. I'm guessing you'll find it in your web.config.

for me, it worked like the following, using packager manager console, I've uninstall the packages, by the following order sequence and I re installed it, it solved my issue..

> Uninstalling

Uninstall-Package Microsoft.AspNet.WebPages.OAuth
Uninstall-Package DotNetOpenAuth.AspNet 
Uninstall-Package DotNetOpenAuth.OpenId.RelyingParty
Uninstall-Package DotNetOpenAuth.OpenId.Core 
Uninstall-Package DotNetOpenAuth.OAuth.Consumer
Uninstall-Package DotNetOpenAuth.OAuth.Core
Uninstall-Package DotNetOpenAuth.core

Build, If you are not using the above packages then this should solve the problem, to Install the above again in case you need it, do the following..

> Reinstall

install-Package DotNetOpenAuth.AspNet 
install-Package Microsoft.AspNet.WebPages.OAuth
install-Package DotNetOpenAuth.OpenId.RelyingParty
install-Package DotNetOpenAuth.OpenId.Core 
install-Package DotNetOpenAuth.OAuth.Consumer
install-Package DotNetOpenAuth.OAuth.Core
install-Package DotNetOpenAuth.core

recommanded:

• go to the bin folder of the project, clear it
• when to publish to the IIS, delete the virtual directory and assign the website again to the IIS, since I faced that issue of having cash in the server which was making the problem...

One more solution option is to have assembly dependency as follows:

<dependentAssembly>
  <assemblyIdentity name="DotNetOpenAuth.AspNet"
                    publicKeyToken="2780ccd10d57b246"
                    culture="neutral" />
  <bindingRedirect oldVersion="0.0.0.0-4.3.0.0" newVersion="4.3.0.0" />
</dependentAssembly>
<dependentAssembly>
  <assemblyIdentity name="DotNetOpenAuth.Core"
                    publicKeyToken="2780ccd10d57b246"
                    culture="neutral" />
  <bindingRedirect oldVersion="0.0.0.0-4.3.0.0" newVersion="4.3.0.0" />
</dependentAssembly>

I do not have the reputation to comment but I can verify that I had this exact problem and Jack gave the correct solution for me. I had recently pressed Add Service Reference and it broke the program with the above error message.

Deleting the _bin_deployableAssemblies folder, and your application's bin folder and then clean and rebuild your application made it work again.

In case this helps anyone - I was unable to uninstall the DotNetOpenAuth components through Nuget, so I resolved this error by deleting them from the references list directly and then re-installing dotnetopenauth through nuget.

I was getting this error as well, but with an ASP.NET MVC 5 project. I solved it by installing the Package DotNetOpenAuth.Mvc5 and calling AsActionResultMvc5() instead of AsActionResult()

For me helped adding to csproj file the following section:

<PropertyGroup>
   <PostSharpHostConfigurationFile>web.config</PostSharpHostConfigurationFile>            
</PropertyGroup>

I had the same problem here. My published web.config didn't have the lines:

  <dependentAssembly>
    <assemblyIdentity name="DotNetOpenAuth.Core" publicKeyToken="2780ccd10d57b246" />
    <bindingRedirect oldVersion="1.0.0.0-4.1.0.0" newVersion="4.1.0.0" />
  </dependentAssembly>

Just added and it worked.

Simply remove BIN folder from wwwroot, and publish again.

I was able to resolved it on my end by removing Microsoft.AspNet.Membership.OpenAuth

I run into this issue when working on updating all of ours libraries. this link helped me fix this issue. https://www.devexpress.com/Support/Center/Question/Details/Q554890/the-could-not-load-file-or-assembly-dotnetopenauth-core-version-4-0-0-0-error-message-is .

Specially I added these binding redirects to my web.config file.

      <dependentAssembly>
    <assemblyIdentity name="DotNetOpenAuth.Core" publicKeyToken="2780CCD10D57B246" culture="neutral" />
    <bindingRedirect oldVersion="1.0.0.0-4.1.0.0" newVersion="4.3.0.0" />
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="DotNetOpenAuth.AspNet" publicKeyToken="2780CCD10D57B246" culture="neutral" />
    <bindingRedirect oldVersion="1.0.0.0-4.1.0.0" newVersion="4.3.0.0" />
  </dependentAssembly>

Remove any Microsoft.Web.WebPages.OAuth dependencies everywhere in your projects.