But if the disc is indeed defective then a customer could simply call Microsoft and they would send out a new one. In the 1980s I had occasion to just call their customer service and tell that a product distributed on 5¼" floppies in the 1.2 MB format would not work with my machine because I had the 5¼" 360 KB format and the 3½" 1.44 MB but nothing in between. All I had to do was give them the registration number over the phone and the new floppies arrived in a week at no extra charge. I can't see why they would have changed their policy in the intervening years.