Finally I got this to work =)

I updated System.Web.Mvc to the latest version, which is 5 and something. After that the error message dissapeared.

Now, I succed to enter episerver GUI, but in edit mode it's all left blank when clicking on CMS > Edit.

In admin mode, an error appear when I try edit something. I believe some episerver dll might be missing. I can see in the control panel that I have EPiServer Shared 1.1.1996.0. At my local machine I've got 

1.1.1997.0. How can that be? Aren't all version updates suppose to be handled by the DLL:s?

The following error is shown in dev-tools:

"TypeError: Cannot read property 'label' of undefined". It refers to widgets.js and dojo.js.

Not coming closer to a solution in this case. =/

About MVC it's wise to make sure you get it from Nuget and that the reference points to /packages folder.

In my working 8.11 I have:

  <package id="Microsoft.AspNet.Mvc" version="5.2.3" targetFramework="net45" />
  <package id="Microsoft.AspNet.Providers.Core" version="2.0.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.Razor" version="3.2.3" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebPages" version="3.2.3" targetFramework="net45" />

Hi Johan,

thanks for your answer.

Can you explain what you mean by "reference points"? In my packages.config it looks as follows:

<package id="Microsoft.AspNet.Mvc" version="5.2.3" targetFramework="net451" />
<package id="Microsoft.AspNet.Providers.Core" version="2.0.0" targetFramework="net451" />
<package id="Microsoft.AspNet.Razor" version="3.2.3" targetFramework="net451" />
<package id="Microsoft.AspNet.WebPages" version="3.2.3" targetFramework="net451" />

If you view the properties of for example System.Web.Mvc below References in your project and look at the Path row it should contain a path for the Packages folder inside your solution.

I think the solution to your problem is more likely something in Web.config. Try setup a fresh MVC site using the Visual Studio add-on  New project -> EPiServer etc and compare it's Web.config to yours.

The thing is, that I got it all working locally on my machine, but not on the server. What I've done is publishing and moving the release version to my server. 

The problem regarding system.web.mvc I did succeed to resolve earlier on today. 

I would argue that something differ between local machine and server. What that might be, I'm unfortunaly clueless at the moment.

Thanks for your previous input Johan.

The solution was, as you mentioned to point the references to the package DLLs instead of the ones in the bin directory.

//Daniel