Well, remember, you did a reinstall, so you have set the files back to the original which did not include the order by clause or the mail recordset...
unless you edited the admin_pm/common/mailing_functions.php to add the order by clause, the recordset you are using and the recordset the pages are using is not the same.
if the admin_pm/common/mailing_functions.php recordset does not include the order by clause, you shouldn't include it when checking the emails.