I suspect the call to new returns an undefined value because it fails. The Net::SMTP docs state:
On failure undef will be returned and $@ will contain the reason for the failure.

You can try to get more information by showing $@: 

$smtp = Net::SMTP->new("$servername", Debug   => 1);
print "$@\n";

[download]

Is $servername a valid remote host?

In reply to Re: Undefined value error by toolic
in thread Undefined value error by clarkmurph

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