Not sure if it's Vista or Windows 7 honestly because it's my dad's computer. When trying to start it up, it displays the error "Missing operating sys".
I looked around for methods to fix this and came across the CD to reinstall it, but couldn't find any instructions. From what I've read/seen, you need simply to insert the CD and start the computer, but the computer doesn't do anything different when I do this. What exactly do I need to do?