The return from SubclassesOf is a collection. To acess the members of the collection, use the in keyword, which you are importing with your

use Win32::OLE qw (in);
[download]

#! perl -slw
use strict;

use Win32::OLE qw (in);
use Data::Dumper;

my $Computer = ".";

my $WMIServices = Win32::OLE->GetObject("winmgmts:\\\\" . $Computer . 
+"\\root\\cimv2");

my $test = $WMIServices->SubclassesOf;

for my $sub ( in $test ) {
    print Dumper $sub;
}
[download]