When I try to add an assembly compiled against the .NET 4.0 framework, my .NET Extensions Manager shows the following error:

Error: File 'D:\Temp\Test\AccountDetails.dll' is not a valid .net assembly.

The same library compiled against .NET 3.5 is accepted as "valid" and is added without any errors.
Is this a limit caused by the SLX version I'm using (7.5.3, german) or is this just because .NET 4.0 is not supported in general, yet?

7.5.x .NET Extensions must be Framework 3.5

7.2.x only supported 2.0

There was also a breaking change from 7.5.3 to 7.5.4... the the dll's that you reference (NetExtensions.Core and NetExtensions.Framework) are not compatible with each other... and throw essentially the same error if you target 7.5.3 and then try to deploy in 7.5.4 or vise-versa.

Hi John,

thx for your answer. Some other sources reported the same. I'm currently trying to get WPF into Slx and that means I definitely can't use WPF4 .

As for the NetExtension.*.dll's: Yes: The dll's rolled out with 7.5.4 are of version "7.5.4", indeed. The ones from 7.5.1 to 7.5.3 are all of version "7.5.1.1742" .

Actually, you can... 3.5 had wpf... although not quite everything was implimented at that point.

I have one working... more or less.

I had to host the wpf inside a winform to get it to behave.

Affirmative: You're limited to WPF 3.5 where the DataGrid is missing and you have to host your WPF control inside a WinForm. But: Did you ever try to use the DataGrid provided by the WPFToolkit (Codeplex)? ... ... No chance to get the assembly reference to WPFToolkit.dll included into your assembly. And so the WPFToolkit.dll will not be added to the dependencies by the .NET Extensions Manager. I think this is a side-effect when framework 4.0 and framework 3.5 is installed on your machine. The DataGrid from WPFToolkit (3.5) uses the same namespace like the DataGrid in WPF4 which is included in framework 4.0 ... have to check this...

Also solved this problem

The bad thing was that I never used any artefacts from WPFToolkit assembly in C#-(.cs-)files (code behind). WPFToolkit was only used in the XAML-file by adding its namespace. The compiler didn't notice that at all. Things definitely changed for good when I just instanciated one single class from the WPFToolkit namespace (as dummy) in my codebehind: The compiled assembly then contained the reference to WPFToolkit.dll and it was imported by .NET Extensions Manager

What finally helped me was the last entry of this post: http://www.slxdeveloper.com/forum.aspx?forumid=2004&;postid=22567 - Thank you Brian