Could not load file or assembly 'System.Web.Mvc' . How to use the correct reference?

I have an application built on ASP.NET web forms which also supports MVC 5. I included MVC 5 API controllers in my project for which I had to upgrade Json from version 4.5 to 7.0. After making those changes when I launched the application, I get the following error:

> Could not load file or assembly 'System.Web.Mvc' or one of its
> dependencies. The located assembly's manifest definition does not
> match the assembly reference. (Exception from HRESULT: 0x80131040)

I checked the reference for `System.Web.Mvc`. In the property dialog run time version is `v4.0.30319` and version is `5.0.0.0`. In web.config, the assemblies are set as the following:

<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="NLog" publicKeyToken="5120e14c03d0593c" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-2.0.1.0" newVersion="2.0.1.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="AntiXssLibrary" publicKeyToken="d127efab8a9c114f" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-4.3.0.0" newVersion="4.3.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>
<!--<dependentAssembly>
<assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-4.5.0.0" newVersion="4.5.0.0" />
</dependentAssembly>-->
<dependentAssembly>
<assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" />
<bindingRedirect oldVersion="0.0.0.0-7.0.0.0" newVersion="7.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>
</assemblyBinding>

The full error log is shown below:


> === Pre-bind state information === LOG: DisplayName = System.Web.Mvc (Partial) WRN: Partial binding information was supplied for an
> assembly: WRN: Assembly Name: System.Web.Mvc | Domain ID: 2 WRN: A
> partial bind occurs when only part of the assembly display name is
> provided. WRN: This might result in the binder loading an incorrect
> assembly. WRN: It is recommended to provide a fully specified textual
> identity for the assembly, WRN: that consists of the simple name,
> version, culture, and public key token. WRN: See whitepaper
>

[To see links please register here]

for more information and
> common solutions to this issue. LOG: Appbase =
> file:///C:/Users/Ahmed/Documents/Visual Studio
> 2013/Projects/MediaSoft/Project/c#/YuClone/YuClone/ LOG: Initial
> PrivatePath = C:\Users\Ahmed\Documents\Visual Studio
> 2013\Projects\MediaSoft\Project\c#\YuClone\YuClone\bin Calling
> assembly : (Unknown).
> === LOG: This bind starts in default load context. LOG: Using application configuration file: C:\Users\Ahmed\Documents\Visual Studio
> 2013\Projects\MediaSoft\Project\c#\YuClone\YuClone\web.config LOG:
> Using host configuration file:
> C:\Users\Ahmed\Documents\IISExpress\config\aspnet.config LOG: Using
> machine configuration file from
> C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
> LOG: Policy not being applied to reference at this time (private,
> custom, partial, or location-based assembly bind). LOG: Attempting
> download of new URL
> file:///C:/Users/Ahmed/AppData/Local/Temp/Temporary ASP.NET
> Files/root/22a49c5f/2f5ffeb9/System.Web.Mvc.DLL. LOG: Attempting
> download of new URL
> file:///C:/Users/Ahmed/AppData/Local/Temp/Temporary ASP.NET
> Files/root/22a49c5f/2f5ffeb9/System.Web.Mvc/System.Web.Mvc.DLL. LOG:
> Attempting download of new URL file:///C:/Users/Ahmed/Documents/Visual
> Studio
> 2013/Projects/MediaSoft/Project/c#/YuClone/YuClone/bin/System.Web.Mvc.DLL.
> LOG: Using application configuration file:
> C:\Users\Ahmed\Documents\Visual Studio
> 2013\Projects\MediaSoft\Project\c#\YuClone\YuClone\web.config LOG:
> Using host configuration file:
> C:\Users\Ahmed\Documents\IISExpress\config\aspnet.config LOG: Using
> machine configuration file from
> C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
> LOG: Redirect found in application configuration file: 5.0.0.0
> redirected to 5.2.3.0. LOG: Post-policy reference: System.Web.Mvc,
> Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 LOG:
> Attempting download of new URL
> file:///C:/Users/Ahmed/AppData/Local/Temp/Temporary ASP.NET
> Files/root/22a49c5f/2f5ffeb9/System.Web.Mvc.DLL. LOG: Attempting
> download of new URL
> file:///C:/Users/Ahmed/AppData/Local/Temp/Temporary ASP.NET
> Files/root/22a49c5f/2f5ffeb9/System.Web.Mvc/System.Web.Mvc.DLL. LOG:
> Attempting download of new URL file:///C:/Users/Ahmed/Documents/Visual
> Studio
> 2013/Projects/MediaSoft/Project/c#/YuClone/YuClone/bin/System.Web.Mvc.DLL.
> WRN: Comparing the assembly name resulted in the mismatch: Minor
> Version ERR: Failed to complete setup of assembly (hr = 0x80131040).
> Probing terminated.



Following is the **Stack Trace**


> [FileLoadException: Could not load file or assembly 'System.Web.Mvc'
> or one of its dependencies. The located assembly's manifest definition
> does not match the assembly reference. (Exception from HRESULT:
> 0x80131040)]
>
> [FileLoadException: Could not load file or assembly 'System.Web.Mvc,
> Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or
> one of its dependencies. The located assembly's manifest definition
> does not match the assembly reference. (Exception from HRESULT:
> 0x80131040)] System.Reflection.RuntimeAssembly._nLoad(AssemblyName
> fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly
> locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder,
> Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean
> suppressSecurityChecks) +0
> System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String
> codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint,
> StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean
> throwOnFileNotFound, Boolean forIntrospection, Boolean
> suppressSecurityChecks) +36
> System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName
> assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly,
> StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean
> throwOnFileNotFound, Boolean forIntrospection, Boolean
> suppressSecurityChecks) +152
> System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString,
> Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr
> pPrivHostBinder, Boolean forIntrospection) +77
> System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString,
> Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean
> forIntrospection) +21 System.Reflection.Assembly.Load(String
> assemblyString) +28
> System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String
> assemblyName, Boolean starDirective) +38
>
> [ConfigurationErrorsException: Could not load file or assembly
> 'System.Web.Mvc, Version=5.2.3.0, Culture=neutral,
> PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The
> located assembly's manifest definition does not match the assembly
> reference. (Exception from HRESULT: 0x80131040)]
> System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String
> assemblyName, Boolean starDirective) +738
> System.Web.Configuration.CompilationSection.LoadAllAssembliesFromAppDomainBinDirectory()
> +217 System.Web.Configuration.CompilationSection.LoadAssembly(AssemblyInfo
> ai) +130
> System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection
> compConfig) +170
> System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromReferencedAssemblies()
> +92 System.Web.Compilation.BuildManager.CallPreStartInitMethods(String
> preStartInitListPath, Boolean& isRefAssemblyLoaded) +290
> System.Web.Compilation.BuildManager.ExecutePreAppStart() +157
> System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager
> appManager, IApplicationHost appHost, IConfigMapPathFactory
> configMapPathFactory, HostingEnvironmentParameters hostingParameters,
> PolicyLevel policyLevel, Exception appDomainCreationException) +531
>
> [HttpException (0x80004005): Could not load file or assembly
> 'System.Web.Mvc, Version=5.2.3.0, Culture=neutral,
> PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The
> located assembly's manifest definition does not match the assembly
> reference. (Exception from HRESULT: 0x80131040)]
> System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9924184
> System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context)
> +101 System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest
> wr, HttpContext context) +261


How do I upgrade the version of System.Web.Mvc to point to the correct assembly?

Error was caused due to incorrect binding. I changed:

<dependentAssembly>
<assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>

to

<dependentAssembly>
<assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.0.0.0" />
</dependentAssembly>

and it works now.

In my case i solved by changing the `PageControls` and `assemblyBinding` elements on config to match the current version of `System.Web.Mvc, wich is 5.2.4.0

**PageControls**

At the `PageControls` section replace the version in **all occurrences** of assembly "System.Web.Mvc", for your current version.:


<pages controlRenderingCompatibilityVersion="4.0" validateRequest="false" pageParserFilterType="System.Web.Mvc.ViewTypeParserFilter, System.Web.Mvc, Version=5.2.4.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" pageBaseType="System.Web.Mvc.ViewPage, System.Web.Mvc, Version=5.2.4.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" userControlBaseType="System.Web.Mvc.ViewUserControl, System.Web.Mvc, Version=5.2.4.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<controls>
<add assembly="System.Web.Mvc, Version=5.2.4.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" namespace="System.Web.Mvc" tagPrefix="mvc"/>
</controls>

**assemblyBinding**

At the `assemblyBinding`element map all previous versions of the assembly to the current version, like this:


<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="0.0.0.0-5.2.4.0" newVersion="5.2.4.0"/>
</dependentAssembly>

This element it is used by any package the references an old version.

**How to check the current version of 'System.Web.Mvc'**

You current version of `System.Web.Mvc` can be seen in properties tab, selecting the assembly from the project references, like this:


[![enter image description here][1]][1]

Note: I am answering an 2 years old question, so reasons for this error occur now may be different

[1]:

In my case the application was working fine locally but not on one of the servers. Removing the <dependentAssembly> section for 'System.Web.Mvc' fixed the issue for me.

Well, it's the *version binding* concern, and for the users getting into this ***now*** as in ***2019***, with say, **VS 2017**, (*as I ran into*) and as the OP mentioned :

> How do I upgrade the version of System.Web.Mvc to point to the correct
> assembly?

Always let `nuget package manager` do it for you, to make the correct versions installed according to your project `.NET` version etc.

Since, I reached here searching for my issue :

> Could not load file or assembly 'System.Web.Mvc, Version=5.2.4.0,
> Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its
> dependencies. The located assembly's manifest definition does not
> match the assembly reference. (Exception from HRESULT: 0x80131040)

and got the indication of version binding concern, I did the following: [![Nuget Mvc Update][1]][1]

and it worked quite smoothly thereafter.

*@Ahmed*, Thanks for pointing to the right direction, though

[1]:

Update the version of `System.Web.Mvc` from NuGet package, it will work properly.

Just uninstall and install the *Microsoft.AspNet.Mvc* in NuGet Packages from Tools Menu:

[![this.][1]][1]


[1]:

Ahmed Mujtaba's solution worked for me when I changed newVersion (back) to 4.0.0.0

I found this error message, when I was trying to publish my solution.
The reason for the problem was the 'System.Web.Mvc' reference version was not similar to my 'web.config' version.
In my case in 'web.config' reference version was 5.2.4.0, but in project it was 5.2.7.0

To fix the error -

1. Go to your project 'References', then find 'System.Web.Mvc'
2. Right click on it to view the property. You will get your 'System.Web.Mvc' version number.
3. Open your 'web.config' file and go to the 'system.web' code block and there you will find your 'System.Web.Mvc' version.
3. If your web.config assembly version, not matched with the project 'References' version.
4. Remove 'System.Web.Mvc' from project 'References'.
5. Install 'System.Web.Mvc' again and make sure the version you installed are the same as on your web.config assembly version.
Sample package manager console command to install Microsoft.AspNet.Mvc. You need to place your desire version no when you run the command-

> Install-Package Microsoft.AspNet.Mvc -Version 5.2.4.0

I don't know if it'll work for you or not. But that's work for me. Thanks