The problem is before your isset... so when you do explode and pass results to list... that expects 6 parametes only receive 5 or less and you get the error.
I suggest the following replacement:
$line = fgets($filePointer); $data=explode("|", $line); while(count($data)<6) $data=""; list($firstName, $lastName, $contactMethod, $phoneMail, $resideCity, $comments) = $data;
That will add enough data for list to set vars.
and should work!