Why do I get a "Bad Gateway" error with my Perl CGI program on IIS?

Question

I'm trying to run sample Perl script on Windows 7 and I configured IIS 7 to allow ActivePerl to run but I'm getting this error:

HTTP Error 502.2 - Bad Gateway
The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are "Hello World. ".

Module  CgiModule
Notification    ExecuteRequestHandler
Handler Perl Script (PL)
Error Code  0x00000000
Requested URL   http://localhost:80/hello.pl
Physical Path   C:\inetpub\wwwroot\hello.pl
Logon Method    Anonymous
Logon User  Anonymous

and here is my Perl script:

#!/usr/bin/perl
print "Hello World.\n";

Answer 1

The first output returned from any CGI program should be the headers.

Try

#!/usr/bin/perl
print "Content-type: text/plain\n\n";
print "Hello World.\n";