CGI development requires that the first thing that your script prints be a properly formatted header so the browser can figure out what kind of an object it is. Generally if you're using CGI, this means that you should "print header;" as early in the program as possible.

This kind of error is usually caused by your script abnormally ending, often because of a file permissions error or some difference between the command-line and web environments. The following code, placed at the top of your script, will help:

use CGI qw(:standard);
use CGI::Carp qw(fatalsToBrowser);
use strict;
print header;
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