App crash on windows 10 mobile

Question

This exception occurs when i try to load my app on my device (lumia 950).

An exception of type 'System.IO.FileLoadException' occurred in Template10Library.DLL but was not handled in user code

Additional information: Could not load file or assembly 'System.Threading, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

The environment : I'm using Template10 as a git submodule in my project instead of as a nuget package. I also have 2 other 'Class Library' projects and 1 'Windows Runtime Component' projects in my solution that my app depends on.

I'm a bit out of my depth here, I'm pretty new to app development and I have no clear understanding on the particulars of the windows build/deploy/runtime environment so I don't really know where to start.

I know you probably require more information in order to help me, so just ask and I'll try to get back to you.

Edit:

I added the following code in my app so that it ran before I got the exception above.

try
{
    var assm = Assembly.Load(new AssemblyName("System.Threading"));
}
catch(Exception e)
{
    System.Diagnostics.Debugger.Break();
}

By pausing the debugger at var assm ... I got the following information from the loaded assembly:

Fullname: "System.Threading, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"

ImageRuntimeVersion: "v4.0.30319"

Location: "C:\\windows\\system32\\SYSTEM.THREADING.NI.DLL"

So what does this mean? That my phone have older versions of system dll's? But why does my app require 4.0.10 when 4.0.0 should suffice?

EDIT 2:

I created a new blank app and a similar problem occured but this time with no library dependencies and this time I tried to use 'System.Net.Http.HttpClient' and I got the following exception:

An exception of type 'System.IO.FileLoadException' occurred in App1.exe but was not handled in user code

Additional information: Could not load file or assembly 'System.Net.Primitives, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

I'm running OS build 10.0.10586.0 but I'm starting to consider that there is something wrong with my device.

Answer 1

Apparently my visual studio installation was messed up... so I did a complete reinstallation of the entire OS, and now it (and my apps) works properly.

Thank you Alan Yao for your input!