Yours
$sql = "update calendar set event = $event', descrip = '$descrip', location_add3 = '$location_add3' where cal_id = $cal_id";
Mine:
$sql = "update calendar set event = '$event', descrip = '$descrip', location_add3 = '$location_add3' where cal_id = $cal_id";
$query = mysql_query("update calendar set event = '$event', descrip = '$descrip', location_add3 = '$location_add3' where cal_id = $cal_id");