I've recently had to replace my Windows XP computer with one that for some reason refuses to run XP (OEM) off my old hard drive (even in safe mode). Though I'm going to attempt a reinstall, being without a Windows XP system has led me to wonder how the heck I'm supposed to make sure my software is compatible with an operating system I don't have access to. I know the answer is to either get a computer that will run it or to find somebody else who owns such a computer, but I'm curious to learn about how each of you approach this and for how many platforms do you do it. Dropping Windows XP support is not an option at this point, though it may be in the future. I need to be able to test my software on Windows XP and am really pissed off at having to replace my old computer. How, then, do you deal with such things?