use strict;
use warnings;
use Net::SSH::W32Perl;

my $host = 'host';
my $pass = 'pwd';
my $user = 'userid';
my $cmd  = 'command';

my $ssh = new Net::SSH::W32Perl(
          $host, 
          debug => 1,
          protocol => 2
);
$ssh->login($user, $pass);

my($stdout, $stderr, $exit) = $ssh->cmd($cmd);
print $stdout, "\n";
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Reading configuration data /.ssh/config
Reading configuration data /etc/ssh_config
Connecting to <hostname>, port 22.
Socket created, turning on blocking...
Remote protocol version 2.0, remote software version OpenSSH_5.2
Net::SSH::Perl Version 1.34, protocol version 2.0.
The getpwuid function is unimplemented at C:/Perl/site/lib/Net/SSH/Per
+l/SSH2.pm
line 39, <GEN0> line 1.
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Cygwin implements getpwuid. If you are using ActiveState, which doesn't implement getpwuid, then you'll probably have to go into the source at C:/Perl/site/lib/Net/SSH/Perl/SSH2.pm with your editor and change sub _proto_init to this

sub _proto_init { 
    my $ssh = shift; 
my $home = $ENV{HOME} || $ENV{USERNAME}; 
    unless ($ssh->{config}->get('user_known_hosts')) { 
        defined $home or croak "Cannot determine home directory, pleas
+e set the environment variable HOME"; 
        $ssh->{config}->set('user_known_hosts', "$home/.ssh/known_host
+s2"); 
}
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my $home should read:

my $home = $ENV{HOME} || $ENV{USERNAME};
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I have fixed this problem on windows, I have defined a enviroment variable HOME.