System.Data Assembly Not found

.net-assembly, c#, system.data

Solution

Add this to app.config..

  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0" />
  </startup>

If you need old versions of dlls to be loaded in a windows service you must add this. For web services iis automatically takes care of it, but not for windows service.

Problem

I have a reference to `System.Data` in my windows service project. I keep getting the `Exception` : Could not load file or assembly 'System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified. I attach the `FusionLog` to my code and found out the following. For `System.Data` only visual studio is looking here: Assembly manager loaded from: C:\windows\Microsoft.NET\Framework\v2.0.50727\mscorwks.dll And it should be looking here (all the other assemblies are but System.Data) Assembly manager loaded from: C:\windows\Microsoft.NET\Framework\v4.0.30319\clr.dll How can I do point my `System.Data` file to look in the right place? My guess is `Microsoft Commerce Server` dlls are referenceing the 2.0 folder maybe.

Original source