Hello philkime,

Recently I was struggling with similar problems and I found that quite a few things can go wrong around using the starttls command.

You can build in extra error checking like how I did it in my recent post in Cool Uses For Perl: here

The code that I took from there shows:

• Sending a HELLO, your server may expect that, note that starttls will send it again
• Check if the connection was actually upgraded.
• Check the contents of $smtp->message()
• See what $@ contains
• (Not shown below) Activate debugging:

  # Activate this line to debug SSL:
  # use IO::Socket::SSL qw(debug4);
  [download]

• (Not shown below): Activate debugging for SMTP by creating the $smtp with Debug => 1

# HELLO
# Reminder: hello is also send again after starttls
$smtp->hello( $cs->{ clientID } )
    or die "Error: " . $smtp->message() ;

# STARTTLS
if ( !$smtp->starttls() ) {
    if ( ref $smtp eq 'Net::SMTP' ) {
        die "NET::SMPT failed to upgrade connection after connection m
+essage: " .
        $smtp->message() .
        "Possible reasons for this may be firewalls or antivirus prote
+ction software (such as mail shields). You can activate debugging for
+ IO::Socket::SSL and \$dbgSMTP to search for other possible reasons\n
+" ;
    } else {
        die "starttls failed with Error: " . $smtp->message() .
        "You can activate debugging for IO::Socket::SSL and \$dbgSMTP 
+to search for possible reasons\n" ;
    }
} ;

# AUTHENTICATE
...

# Finish with this line, it may contain extra error info

if($@) {
    print STDERR "Error sending mail: $@";
}
[download]

Let us know what you find,

Veltro

edit: In case your $smtp object is a 'Net::SMTP_auth', then you need to change the line: if ( ref $smtp eq 'Net::SMTP' ) { to if ( ref $smtp eq 'Net::SMTP_auth' ) {. But now I am thinking again about this, here may actually be your problem. The auth method is not the one you think you are calling! Because after starttls the $smpt object is a Net::SMTP::_SSL (unless this was solved differently for Net::SMTP_auth)