作者：jiankunking 出处：http://blog.csdn.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&webp=1 "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&webp=1 "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！