Remove the error suppression and you might actually see an error message. Better, yet, check for one.
<?php require_once('../Connections/connection.php'); ?>
<?php
if ($result = mysql_query( "select yearID, year, from sss.years")) {
if (mysql_num_rpws($result)) {
print "<p>Select a year:\n";
print "<select name=\"yearID\">\n";
while ($row = mysql_fetch_assoc($result)) {
$yearID = $row[ 'yearID' ];
$year = $row[ 'year' ];
print "<option value=$yearID>$year\n";
}
print "</select>\n";
print "</p>\n";
} else {
// no record found.
}
} else {
trigger_error(mysql_error());
}