Could not load file or assembly 'Newtonsoft.Json, Version=9.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed' or one of its dependencies

I have a WinJS project that is previously built on Windows 8.1 using VS 2013.

Recently I upgraded this project to Universal Windows 10 by creating a blank Javascript Universal windows 10 project and then added all my files from old project.

I have Windows Runtime Components and also Class Library for SQLite.

I added Universal Windows Runtime Component and Universal Class Library and copied all my files from old project to respective places.

Somehow I managed to remove all the build errors.

I installed all the required SQLite-net, SQLite for Universal Windows Platform, Newtonsoft, etc.

But when I run the application and call a Native method in Windows Runtime Component it gives some kind of strange errors as:

An exception of type 'System.IO.FileNotFoundException' occurred in mscorlib.ni.dll but was not handled in user code.

Additional information: Could not load file or assembly 'Newtonsoft.Json, Version=9.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed' or one of its dependencies. The system cannot find the file specified.

enter image description here

Newtonsoft version is: 9.0.1

My project.json file of Windows Runtime Component has following:

  {
  "dependencies": {
    "Microsoft.NETCore.UniversalWindowsPlatform": "5.0.0",
    "Newtonsoft.Json": "9.0.1"
  },
  "frameworks": {
    "uap10.0": {}
  },
  "runtimes": {
    "win10-arm": {},
    "win10-arm-aot": {},
    "win10-x86": {},
    "win10-x86-aot": {},
    "win10-x64": {},
    "win10-x64-aot": {}
  }
}

My Visual Studio version is:

enter image description here

I tried removing all the Newtonsoft json and re-installing it but no luck.

Solution 1:

I solved this problem by adding Newtonsoft.Json to the NuGet of the startup project (even though it is not directly used in the startup project).

Solution 2:

I made a basic Demo and reproduced this problem. It seems that WinRT component failed to find the correct assembly of Newton.Json. Temporarily the workaround is to manually add the Newtonsoft.json.dll file. You can achieve this by following steps:

Right click References-> Add Reference->Browse...-> Find C:\Users\.nuget\packages\Newtonsoft.Json\9.0.1\lib\portable-net45+wp80+win8+wpa81\Newtonsoft.json.dll->Click Add button.
Rebuild your Runtime Component project and run. This error should be gone.

Solution 3:

I had the same issue too, to solve this, check in References of your project if the version of Newtonsoft.Json was updated (probablly don´t), then remove it and check in your either Web.config or App.config wheter the element dependentAssembly was updated as follows:

<dependentAssembly>
  <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
  <bindingRedirect oldVersion="0.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
</dependentAssembly>

After that, rebuild the project again (the dll will be replaced with the correct version)

Solution 4:

I am using Visual Studio 2013 Update 2. In my case, I have a web project and a Web Api project and unit test project and other class libraries in a single solution.

I've spent couple of days to solve the problem. Below is the step-by-step solution that I have found.

Right click on Web Api project. Select "Set as StartUp Project"
Right click on Web Api project. Go to Properties ( Alt + Enter ).
On the Application tab on left hand side menu, select Application
Find Target framework. Change it to 4.5.1 and save. However, it is showing error in "Error List" window. After Rebuild, there is no error.
Remove all Newtonsoft.Json packs from solution by using below query from Package Manager Console ( to get it View > Other Window > Package Manager Console ).

uninstall-package newtonsoft.json -force

Reinstall Newtonsoft.Json from Package Manager Console

install-package newtonsoft.json

If you have latest update for Visual Studio 2013, you might not encounter with this problem. As I am using Update 2, so, while trying to install Newtonsoft.Json, I have encountered with the following error.

The 'Newtonsoft.Json 10.0.3' package requires NuGet client version '2.12' or above, but the current NuGet version i s '2.8.50313.46'

To solve this problem, we need to update the Package Manager Console. Got to

Tools > Extensions and Updates... > In left pane.. select Updates > Visual Studio Gallery.

Update the NuGet Package Manager Extension. Follow the steps that are coming afterwards.
Visual Studio will take a restart after that.
Execute step 6 again.

After Installation packages.config will be added with this below line

  <package id="Newtonsoft.Json" version="10.0.3" targetFramework="net451" />

After installation web.config will be added with this below lines

<dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-10.0.0.0" newVersion="10.0.0.0" />
</dependentAssembly>

It will execute successfully, if there is no other error.

Solution 5:

I had a similar problem with a new ASP.NET Core application a while ago. Turns out one of the referenced libraries used a version of Newtonsoft.Json that was lower than 9.0.0.0. So I upgraded the version for that library and the problem was solved. Not sure if you'll be able to do the same here