Configured impersonation is the simplest form of impersonation. You have to use the web.config file to define the impersonation behavior you want, by adding the <identity> element as shown:
<!– Other settings omitted. –>
<identity impersonate=”true” />
You can configure the <identity> element in more than one way, depending on the result you want:
– If you want to impersonate the Windows account authenticated by IIS – just set the impersonate attribute to true as shown above.
– If you allow anonymous access, you can use the IUSR_[ComputerName] account. In this case the impersonated account must have all the permissions required to run ASP.NET code, including read-write access to the c:\[WinDir]\Microsoft.NET\Framework\[Version]\Temporary ASP.NET Files directory where the compiled ASP.NET files are stored. Otherwise, an error will occur and the page will not be served.