use Win32;
use Win32::API;
use Win32::OLE qw( in );

my $machine = ".";
my $WMIServices = Win32::OLE->GetObject ( "winmgmts:{impersonationLevel=impersonate,(security)}//$machine/root/cimv2" ) || die;

my $objVariable = $WMIServices->Get("Win32_Environment")->SpawnInstance_;
$objVariable->{Name}="NewOSType";
$objVariable->{UserName} = "<System>";
$objVariable->{VariableValue} = "LAMBDA";
$objVariable->Put_;