具体步骤如下：

1、快捷键：Ctrl + R

2、输入：%windir%\System32\inetsrv\config\applicationHost.config

3、注销：fileExtensions节下的：<!--<add fileExtension=".config" allowed="false" /> --> 和 hiddenSegments 节下的<!-- <add segment="web.config" /> -->。具体如下：

    
        
     
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                       
                      
                      
     
                           
                           
                           
                           
                           
                           
                           
                           
                       
                  
     4、点击网站XXX，在右侧的IIS栏里，双击MIME类型项，在新打开的对话框中右侧（右击）点击添加，类型如：.config  MIME类型如：xml/txt 完毕后就可以浏览web.config了，浏览其他后缀步骤更简单。。。