Oops I may have missed out some important information. This my code now:

use CGI;
use Win32::ODBC;
use Time::Local;

  if (!($db=new Win32::ODBC($DSN))) {
    print "Error connecting to Database\n";
    print "Error: " . Win32::ODBC::Error() . "\n";
  }
$SqlStatement = "SELECT StaffNo FROM FOSInput WHERE Username=\'$ntuser
+'\)";
    if ($db->Sql($SqlStatement)) {
    print "SQL failed.\n";
    print "Error: " . $db->Error() . "\n";
    if ($DebugMode) {
      print "<HR>$SqlStatement<HR>"; # Debug
    }
  }
  else  {
    while($db->FetchRow()) {
  print "<form><select name=\"month\" size=\"1\">\n";
  print "<option value=\"\">Select a month</option>\n";
  print "<option value=\"0305\">March 2005</option>\n";
  print "<option value=\"0405\">April 2005</option>\n";
  print "<option value=\"0505\">May 2005</option>\n";
  print "<option value=\"0605\">June 2005</option>\n";
  print "<option value=\"0705\">July 2005</option>\n";
  print "</select><input type=\"submit\"></form>\n";

print "At end of Input field\n";
my $filename= $cgi->param('month');
print "$filename\n";

    }
 }
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I've gone for hard coding the drop down but when I select a month, the page just kind of refreshes, I get the 'At end of Input field' message but $filename isn't printed. What gives?