Update to .Net 3.5

Posted on 2008-11-11
Last Modified: 2013-11-08
I updated to the .NET 3.5 framework.

I now get the following compile error when I build my C# project.

How can I fix this ?

Error      1      
The type 'System.Web.Script.Services.ScriptServiceAttribute' 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\\System.Web.Extensions.dll'      C:\Src\App_Code\iProfileProxy.cs      21      29      C:\Src\
Question by:pillmill
    LVL 19

    Accepted Solution


    This is a know problem that has a fix :
    look at the "Make sure you install the MS AJAX Patch" section

    Author Comment


    Thanks. I ran the MS AJAX patch script, but I have the same error
    when I compile my project.

    Author Comment

    I removed earlier versions of .NET framework, but now get the error:

    Error      1      Could not load file or assembly 'System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.      C:\Src\web.config      68      

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