作者：jiankunking 出处：http://blog.****.net/jiankunking
今天在本地安装iis。搭建站点，应用程序的时候报错以下的错误：
server错误
Internet Information Services 7.5
错误摘要
HTTP 错误 500.19 - Internal Server Error
无法訪问请求的页面，由于该页的相关配置数据无效。
具体错误信息
模块 IIS Web Core
通知 BeginRequest
处理程序 尚未确定
错误代码 0x80070032
配置错误 无法读取配置节“system.web.extensions”，由于它缺少节声明
配置文件 \\?\E:\12.service\AMACService\web.config
请求的 URL http://localhost:8088/AMACService/AMACService.svc
物理路径 E:\12.service\AMACService\AMACService.svc
登录方法 尚未确定
登录用户 尚未确定
配置源
25: </system.web>
26: <system.web.extensions>
27: <scripting>
链接和很多其它信息
当读取 Web server或 Web 应用程序的配置文件出现故障时，就会发生此错误。在某些情况下，事件日志会包括有关导致此错误的原因的很多其它信息。 查看很多其它信息 »
执行环境先检查下：
1.已经安装.net 4.0执行库
2.设置站点基于.net4.0
![IIS 无法读取配置节"system.web.extensions",由于它缺少节声明](https://image.shishitao.com:8440/aHR0cHM6Ly9iYnNtYXguaWthZmFuLmNvbS9zdGF0aWMvTDNCeWIzaDVMMmgwZEhBdmFXMW5MbUpzYjJjdVkzTmtiaTV1WlhRdk1qQXhOakF4TWpBeE1UUXpNVEV5TVRJL2QyRjBaWEp0WVhKckx6SXZkR1Y0ZEM5aFNGSXdZMFJ2ZGt3eVNuTmlNbU4xV1ROT2EySnBOWFZhV0ZGMkwyWnZiblF2TldFMlREVk1NbFF2Wm05dWRITnBlbVV2TkRBd0wyWnBiR3d2U1RCS1FsRnJSa05OUVQwOUwyUnBjM052YkhabEx6Y3dMMmR5WVhacGRIa3ZRMlZ1ZEdWeS5qcGc%3D.jpg?w=700 "IIS 无法读取配置节"system.web.extensions",由于它缺少节声明")
3.改动“托管管道模式”，Set the Manage Pipeline mode from Integrated to Classic （由集成到经典）
然并软。问题还是没有解决。
最后在微软的论坛找到了解决的办法：
This is because config section hasn't declared. in 4.0 webconfig you have to add it manually.
<configSections>
<sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
<sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerializationSection, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="Everywhere"/>
<section name="profileService" type="System.Web.Configuration.ScriptingProfileServiceSection, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
<section name="authenticationService" type="System.Web.Configuration.ScriptingAuthenticationServiceSection, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
<section name="roleService" type="System.Web.Configuration.ScriptingRoleServiceSection, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
</sectionGroup>
</sectionGroup>
</sectionGroup>
</configSections>
![IIS 无法读取配置节"system.web.extensions",由于它缺少节声明](https://image.shishitao.com:8440/aHR0cHM6Ly9iYnNtYXguaWthZmFuLmNvbS9zdGF0aWMvTDNCeWIzaDVMMmgwZEhBdmFXMW5MbUpzYjJjdVkzTmtiaTV1WlhRdk1qQXhOakF4TWpBeE1UVXdORGMyTlRnL2QyRjBaWEp0WVhKckx6SXZkR1Y0ZEM5aFNGSXdZMFJ2ZGt3eVNuTmlNbU4xV1ROT2EySnBOWFZhV0ZGMkwyWnZiblF2TldFMlREVk1NbFF2Wm05dWRITnBlbVV2TkRBd0wyWnBiR3d2U1RCS1FsRnJSa05OUVQwOUwyUnBjM052YkhabEx6Y3dMMmR5WVhacGRIa3ZRMlZ1ZEdWeS5qcGc%3D.jpg?w=700 "IIS 无法读取配置节"system.web.extensions",由于它缺少节声明")
如上加入后，在iis7的管理介面不再报错！