Blame the vendor
I don't understand companies that behave like that. I'm a freelance programming consultant. When one of my customers calls to complain about the behavior of one of my programs, I'm damn well going to find out what's going on and what I can do about it. If I do find out that the customer's network configuration is the basis of the problem, I'm not going to lay blame, I'll just explain the situation and what I can do to fix it.
In an entirely different domain, my shower has recently developed trouble in getting hot water. The best I could get was a tepid shower. I called the artisan who installed the equipement and asked him to come over and and fix the issue. He was there the next day and, following my explanations, had already pretty much figured out the problem. He had come with a replacement piece of equipment but, instead of just replacing the faulty piece, he audited the entire bathroom. From that, we found that the hot water balloon was making the water too hot which, in turn, was dilating the joint in the shower's temperature dial which, in the end, was rendered incapable of delivering the desired temperature. We agreed that, apart from replacing the faulty piece of equipment, he would also set the balloon to a lower temperature that would avoid creating problems in the future.
What I want to demonstrate here is that a true professional is going to do his best to ensure that the customer is satisfied when he leaves. It requires dedication and knowledge of all the areas in connection to the one you're called in to work on, but such a person is priceless.
Companies are not priceless. What does that say about where we're going ?