If you are setting 'Errmode' parameter of 'Net::Telnet' module as 'return', whenever the script encounter a problem, objet will return an error message and same can be get by calling 'errmsg' function. Please check the below mentioned sample for more details 
use Net::Telnet;
my $telnet = new Net::Telnet ( Timeout=>10, Port=>80, Errmode => 'retu
+rn' );
$telnet->open("testerrmode.com");
if($telnet->errmsg ) {
        print "errmsg: " . $telnet->errmsg . "\n";
} else {
        print "success\n";
}

print "moving to next statement\n";

[download]
If you are setting the 'Errmode' parameter of 'Net::Telnet' module as 'die', use 'eval' function for catching the error string. Please check the code given below 
use Net::Telnet;
eval {
        my $telnet = new Net::Telnet ( Timeout=>10, Port=>80, Errmode 
+=> 'die' );
        $telnet->open("testerrmode.com");
};
if($@) {
        print $@;
} else {
        print "success\n";
}

print "moving to next statement\n";

[download]

In reply to Re: Trying to capture error message using telnet::net by lamp
in thread Trying to capture error message using telnet::net by tprizler

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