$code = lc($code);
	
	warn "$code  $crypt\n" if($self->debug() >= 2);

	my $current_time = time;
	my $return_value = 0;
	my $database_file = File::Spec->catfile($self->data_folder(),"codes.txt");

	# create database file if it doesn't already exist
	$self->_touch_file($database_file);

	# zeros (0) and ones (1) are not part of the code
	# they could be confused with (o) and (l), so we swap them in
	$code =~ tr/01/ol/;

	my $md5 = md5_hex($code);
	
	# pull in current database
	warn "Open File: $database_file\n" if($self->debug() >= 2);
	open (DATA, "<$database_file")  or die "Can't open File: $database_file\n";
		flock DATA, 1;  # read lock
		my @data=<DATA>;
	close(DATA);
	warn "Close File: $database_file\n" if($self->debug() >= 2);

	my $passed=0;
	# $new_data will hold the part of the database we want to keep and 
	# write back out
	my $new_data = "";
	my $found;
	foreach my $line (@data) 
	{
		$line =~ s/\n//;
		my ($data_time,$data_code) = split(/::/,$line);
		
		my $png_file = File::Spec->catfile($self->output_folder(),$data_code . ".png");
		if ($data_code eq $crypt)
		{
			# the crypt was found in the database
			if (($current_time - $data_time) > $self->expire())
			{ 
				 warn "Crypt Found But Expired\n" if($self->debug() >= 2);
				# the crypt was found but has expired
				$return_value = -1;
			} else {
				warn "Match Crypt in File Crypt: $crypt\n" if($self->debug() >= 2);
				$found = 1;
			}
			if ( ($md5 ne $crypt) && ($return_value != -1) && $self->keep_failures())
			{	# solution was wrong, not expired, and we're keeping failures
				$new_data .= $line."\n";
			} else {
				# remove the found crypt so it can't be used again
				warn "Unlink File: " . $png_file . "\n" if($self->debug() >= 2);
				unlink($png_file) or carp("Can't remove png file [$png_file]\n");
			}
		} elsif (($current_time - $data_time) > $self->expire()) {
			# removed expired crypt
			warn "Removing Expired Crypt File: " . $png_file ."\n" if($self->debug() >= 2);
			unlink($png_file) or carp("Can't remove png file [$png_file]\n");
		} else {
			# crypt not found or expired, keep it
			$new_data .= $line."\n";
		}
	}

	if ($md5 eq $crypt)
	{
		warn "Match: " . $md5 . " And " . $crypt . "\n" if($self->debug() >= 2);
		# solution was correct
		if ($found)
		{
			# solution was correct and was found in database - passed
			$return_value = 1;
		} elsif (!$return_value) {
			# solution was not found in database
			$return_value = -2;
		}
	} else {
		warn "No Match: " . $md5 . " And " . $crypt . "\n" if($self->debug() >= 2);
		# incorrect solution
		$return_value = -3;
	}

	# update database
	open(DATA,">$database_file")  or die "Can't open File: $database_file\n";
		flock DATA, 2; # write lock 
		print DATA $new_data;
	close(DATA);
	
	return $return_value;
}

sub _touch_file
{
	ref(my $self = shift) or croak "instance variable needed";
	my $file = shift;
	# create database file if it doesn't already exist
	if (! -e $file)