JavaScriptSerializer Error Message - Duplicate type, how do I resolve?

Question

Hi,

I'm trying to serialize some strings and return through an ajax call and I'm seeing an odd error. Any help would be very much appreciated:

Compiler Error Message: </b>CS0433: 
The type 'System.Web.Script.Serialization.JavaScriptSerializer' exists in both
 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\1.0.61025.0__31bf3856ad364e35\System.Web.Extensions.dll' and
 'c:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll'

Many thanks.

Chris.

Answer 1

I am having this same issue, did you ever find a resolution?