Method 'get_EnableCdn' in type 'System.Web.UI.ScriptManager' from assembly 'System.Web.Extensions' does not have an implementation

Question

Can anyone explain a parse error like this one:

\"Method \'get_EnableCdn\' in type \'System.Web.UI.ScriptManager\' from assembly \'System.Web.Extensions,

Answer 1

I have seen this error in a web application that was upgraded from a Visual Studio 2005 project to a Visual Studio 2010 project.

The solution was to remove the following section from the web.config file:

<runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
        <dependentAssembly>
            <assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35"/>
            <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
        </dependentAssembly>
        <dependentAssembly>
            <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35"/>
            <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
        </dependentAssembly>
    </assemblyBinding>
</runtime>

Answer 2

If you are actually using .NET framework 4.0 + then then fair enough, however if you are simply moving an existing application from say a Windows Server 2003 box to Windows Server 2012 then you can change the application pool that new site site is running under from .NET Frawework 4.0 to 2.0 and the pipeline mode from Integrated to Classic. New sites on Windows Server 2012 default to .NET 4.0 & Integrated