When you deploy a new Web Forms target, a temp directory is created in the Inetpubwwwrootapplication_name
directory, where application_name is the name of your application, and several subdirectories are created in the Inetpubwwwrootapplication_name_root directory.

Files are written to and deleted from these directories, therefore the IIS_IUSRS group must have full permissions on temp and
application_name_root.