LOI_ASP.NET rất rất là kỳ cục

Mình làm Web bằng ASP.NET cơ sở dữ liệu là SQL SERVER,
web mình làm đã hoàn thành, nhưng mà khi cho duyệt thì lúc nó chạy rất tôt nhưng khi up lên host thì bị thông báo như sau :

Server Error in '/' Application.
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Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.

Parser Error Message: 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:domainsductanlong.comwwwrootweb.config line 80)

Source Error:


Line 78: <httpModules>
Line 79: <add name="RadUploadModule" type="Telerik.Web.UI.RadUploadHttpModule, Telerik.Web.UI"/>
Line 80: <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
Line 81: </httpModules>
Line 82: </system.web>


Source File: c:domainsductanlong.comwwwrootweb.config Line: 80


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Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832
__________________________________________________ ___________________________
Minh đóng những dòng báo lỗi vào thì kết quả là như thế này:
Server Error in '/' Application.
--------------------------------------------------------------------------------

Parser Error
Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.

Parser Error Message: 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.

Source Error:


[No relevant source lines]


Source File: none Line: 0

Assembly Load Trace: The following information can be helpful to determine why the assembly 'System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' could not be loaded.


WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLMSoftwareMicrosoftFusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLMSoftwareMicrosoftFusion!EnableLog].




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Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832

Trường hợp như vậy là sao,cứu mình với người ta đang giục gấp gấp....
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