System.Web.Extensions Assembly cannot be resolved

Question

I am trying to run a .NET 4.0 Console application that references a sister library project (Bar.dll) which itself references System.Web.Extensions in VS2010 B2. I am currently only interested in getting access to System.Web.Scripting.JavaScriptSerializer.

Both projects have references to System.Web.Extensions (using the one listed under ".NET" in the App References dialog), but when I try to compile/run the application, the compiler barks:

C:\Windows\Microsoft.NET\Framework\v4.0.21006\Microsoft.Common.targets(1291,9):
warning MSB3253: The referenced assembly "Bar.dll" could not be resolved because it has a dependency on 
"System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
which is not in the currently targeted framework ".NETFramework,Version=v4.0,Profile=Client".

Seriously? What's going on? Why won't the compiler link with the assembly?

After look at the "Add References" dialog again, I see that System.Web.Extensions is built against v2.0.50727. OK, so that's probably the problem. But what assembly holds System.Web.Scripting.JavaScriptSerializer now? — Frank Krueger

itowlson itowlson · Accepted Answer · 2010-01-01T02:33:14

currently targeted framework ".NETFramework,Version=v4.0,Profile=Client".
                                                         ^^^^^^^^^^^^^^

You're targeting the Client Profile, which doesn't include the Web assemblies. Go into Project > Properties > Application and change Target Framework to ".NET Framework 4".

System.Web.Extensions Assembly cannot be resolved

1 Answers