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I just downloaded and am trying to run the sample web site

Topics: Developer Forum
Mar 12, 2010 at 7:48 PM

I created a new asp web site and imported all the files in the sample diectory (app_data, bin, web config), and when I try to compile I get the folowing 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:\Users\Scott Olle\Documents\Visual Studio 2008\WebSites\WebSite7\web.config 22 

I am using .net 3.5 so when I changed it to

<add assembly="System.Web.Extensions, Version=, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>

in the web.config file things got even worse.

What am I missing?  Could I change all the references to 3.5 references?

Thank you


Mar 17, 2010 at 10:44 PM

I had the same problem. You will need to change the System.Web.Assembly back to the original 1.0. Then load System.Web.Extensions.dll and System.Web.Extensions.Design.dll into the bin directory of the sample. If you have installed AJAX 1.0, the dlls are found in Program Files\Microsoft ASP.NET\ASP.NET AJAX Extensions\V1.0.61025 If you didn't install AJAX 1.0, do so. It can coexist with .NET 3.5. Even though the installation installed System.Web.Extensions in my GAC, the sample wouldn't work until I installed the dlls in the bin folder. Hope this helps.


Mar 14, 2011 at 1:57 PM

Based on what rjruud wrote, I searched for System.Web.Extensions.dll and System.Web.Extensions.Design.dll and found them at C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5.  I copied them to "bin" and changed the version in "add assembly" to  I've gotten farther but am getting a System.Net.Sockets.SocketException.  Not sure if this is because System.Web.Extensions is not loaded right or something else.  If anyone has any suggestions, I'd appreciate them.