I've learned just enough Perl to write the following program so I'm probably making a basic mistake. The program is designed to be called from a page by an image tag. It first checks for an existing cookie. If there's a cookie it just returns the GIF. If there's no cookie then it checks for the referer, sets the cookie and then returns the GIF. The problem comes when checking for an existing cookie. If I remove the conditional at 1 & 2 which checks for a cookie, the program runs fine. It sets the cookie and returns the image. If left in I get a "500" error. 
            #!/usr/bin/perl 
            # cset.cgi - set a cookie 
            use CGI::Carp qw(fatalsToBrowser); 
            use CGI qw(:standard); 

            # check for cookie, if no cookie then check for referer
            # and set cookie 
            unless ($ENV{'HTTP_COOKIE'}) { # 1 
            if ($ENV{'HTTP_REFERER'} eq "") { 
            $referer = "None" 
            } 
            else { 
            $referer = $ENV{'HTTP_REFERER'} 
            } 
            $name = "Thanks"; 
            $to_set = cookie(-name => $name, 
            -value => $referer, 
            -expires => "+30d", 
            ); 

            print header(-cookie => $to_set); 

            }                               # 2 
            #print clear GIF 
            $image = "logo.gif"; 
            print img {src=>$image}; 

            <IMG SRC=$image>

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In reply to Conditional statement problem by Anonymous Monk

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