PHP Mailer Error: Message was not sent Mailer Error: Language string failed to load: recipients_failed

PLEASE HELP!!  This is the most frustrating thing I've encountered in a long time.  I'm using PHP and phpmailer.  My application has worked fine for a long time.  Then, the admins upgraded to PHP v5.0.1 and everything quit working.  I've examined all the PHP config variables and reset everything that looked necessary, but my mail forms still don't work.  I also believe the admins implemented SMTP authentication which may be impacting me.

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My code looks like this:

  $mail = new PHPMailer();
  $mail->Encoding = "8bit";
  $mail->CharSet = "iso-8859-1";
  $mail->From = "$EMAIL1";
  $mail->FromName = "$MYNAME";
  $mail->AddAddress("$submittal_email_addresses", "name");
  $mail->Subject = "Contact Message";
  $mail->Body = "Name: $MYNAME\nPhone: $CONTACT_PHONE\nEmail: $EMAIL1\nComments:\n$theCOMMENTS\n\n";

if(!$mail->Send())
{
   echo "There was an error sending the message";
   echo "Mailer Error: " . $mail->ErrorInfo;
   exit;
}

echo "Message was sent successfully";

}
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My error is this:
   Mailer Error: Language string failed to load: instantiate

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I've tried many, many suggested changes I've found on the web including the following:

With:      $mail->IsSendmail();
Get:      Mailer Error: Language string failed to load: execute/usr/sbin/sendmail

With:       Adding  $mail->SetLanguage("en", "phpmailer/language/");
Get:      Mailer Error: Could not instantiate mail function.

With:      $mail->port = 25;
$mail->helo = '';
$mail->auth = TRUE;
$mail->user = 'me@domain.org';
$mail->pass = 'xxxxxxxxxxxxxx';
Get:      Mailer Error: Language string failed to load: instantiate

With:      {above}, plus
               $mail->IsSMTP();
Get:      Warning: fsockopen() [function.fsockopen]: unable to connect to localhost:25 (A non-blocking socket operation could not be completed immediately. ) in D:\path\phpmailer\class.smtp.php on line 105
There was an error sending the messageMailer Error: Language string failed to load: connect_host

With:      {above}, plus
$mail->Host = "domain.org";
$mail->SMTPAuth = TRUE;
$mail->username = 'me@domain.org';
$mail->password = 'xxxxxxxxx';
Get:      Mailer Error: Language string failed to load: from_failed me@domain.org

With:      {above}, plus
$mail->From = "me@domain.org";
Get:      Mailer Error: Language string failed to load: from_failed me@domain.org

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Please HELP!  Thanks!