Unfortunately, IIS doesn't respect the shebang in CGI or ISAPI mode. One can change the CGI association from C:\Perl\bin\perl.exe "%s" %s to C:\Perl\bin\perl.exe -T "%s" %s -- but that may break other scripts, as it turns tainting on for all Perl scripts. Also, it can be very hard to do that when one doesn't have admin rights on a given server, but still wants to use the benefits associated with tainting.