You are printing a HTTP header, but not specifying the content type, so it's defaulting to text/html. A PDF is neither text or HTML.

print $cgi->header("Content-type: application/pdf");

This is explained in the links I gave you over a week ago when you asked in the chatterbox, before you showed any code. Even if you only read the troubleshooting section Getting Your CGI Scripts Working it explains this.

In reply to Re: How to make work HTML::HTMLDoc on browser? by marto
in thread How to make work HTML::HTMLDoc on browser? by elavarasan

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