Failed to load file or assembly SYSTEM.WEB.EXTENSIONS workaround

Recent project Discovery failed to load file or assembly errors because of the reason why Ajax is not installed on my machine. After the problem is resolved, organize as follows:
Performance:
1, "System.Web.Extensions, version=1.0.61025.0, culture=neutral, publickeytoken=31bf3856ad364e35" or one of its dependencies. The system cannot find the file specified.

2, backstage system even if the reference is added, whether the reference is a system or a user, their properties and methods are not recognized;

Solution One:

1, if your program runs on the server you can control, then the installation of ASP. NET AJAX, which is System.Web.Extensions and other DLLs as the GAC deployment; (General installation of Ajax can be solved)
2, if your program runs on the virtual host (not authorized to install the program), then need to put System.Web.Extensions.dll and System.Web.Extensions.Design.dll
(usually in C:\Program Files\Microsoft Asp.net\asp.net 2.0 AJAX Extensions\ v1.0.61025 directory) 2 DLLs are copied to the bin directory of your Web program, which is an application-level deployment.
Also note that you want to check the code in Web. config:

<assemblies>
<add assembly= "System.Web.Extensions, version=1.0.61025.0, culture=neutral, publickeytoken=31bf3856ad364e35"/ >
</assemblies>
<controls>
<add tagprefix= "Atlas" namespace= "System.Web.UI" assembly= "System.Web.Extensions, version=1.0.61025.0, culture= Neutral, publickeytoken=31bf3856ad364e35 "/>
</controls>

Solution Two:

1. Open Web. config to find the following related nodes:
<add assembly= "System.Web.Extensions, version=3.5.0.0, culture=neutral, publickeytoken=31bf3856ad364e35"/>
<add assembly= "System.Web.Extensions, version=1.0.61025.0, culture=neutral, publickeytoken=31bf3856ad364e35" ></add>
<add assembly= "System.core, version=3.5.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>
<add assembly= "System.Data.Linq, version=3.5.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>
<add assembly= "System.Web.Extensions, version=3.5.0.0, culture=neutral, publickeytoken=31bf3856ad364e35"/>
<add assembly= "System.core, version=3.5.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>
<add assembly= "System.Data.Linq, version=3.5.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>
2. Comment out or delete these results, then recompile.

This is because VS2005 compiled Ajax is 1.0, and VS2008 can compile AJAX1.0 and other versions at the same time. So there will be conflicts.

Solution Three:

Publickeytoken=31bf3856ad364e35 "
Or one of its dependencies. The system cannot find the file specified
Install the ASP. X:\Program Files\Microsoft Asp.net\asp.net 2.0 Ajax extensions\v1.0.61025
The System.Web.Extensions.Design.dll file in the directory is added to the bin directory of the project, and the file is copied to the site Bin directory and then run again.
There will be three DLL files after installing ASP.

System.Web.Extensions.Design.dll

AjaxExtensionsToolbox.dll

System.Web.Extensions.dll

In general, these three files should be added to the project Bin directory, to be insured, all copied into it

Failed to load file or assembly SYSTEM.WEB.EXTENSIONS workaround