Access to the temp directory is denied

j今天突然好几个网站不能访问，报如下错误，其中default为用用程序池。

Access to the temp directory is denied.  Identity 'IIS APPPOOL\default' under which XmlSerializer is running does not have sufficient permission to access the temp directory.  CodeDom will use the user account the process is using to do the compilation, so if the user doesn�t have access to system temp directory, you will not be able to compile.  Use Path.GetTempPath() API to find out the temp directory location.

网上搜索解决办法时找到相同错误并解决办法：

创建 BlogConfigurationSettings 的配置节处理程序时出错: 拒绝访问临时目录。以其运行 XmlSerializer 的身份“IIS APPPOOL\www.cnblogs.com”没有足够的权限访问临时目录。CodeDom 将使用此进程用于进行编译的用户帐户，因此如果用户对系统临时目录没有访问权限，则将无法编译。使用 Path.GetTempPath() API 可找到临时目录位置。

Access to the temp directory is denied.  Identity 'IIS APPPOOL\www.cnblogs.com' under which XmlSerializer is running does not have sufficient permission to access the temp directory.  CodeDom will use the user account the process is using to do the compilation, so if the user doesnt have access to system temp directory, you will not be able to compile.  Use Path.GetTempPath() API to find out the temp directory location.

CS0016: 未能写入输出文件“c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\946055b8\92eead15\App_global.asax.qakaesxx.dll”--“拒绝访问。 ”

开始以为是“C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files”文件夹权限的问题，但怎么设置这个权限也解决不了问题。

后来在应用程序池设置中将“加载用户配置文件”（Load User Profile）设置为true，问题就解决。