People prefer more to Window 7 than vista as it is more compatible than vista. It has been observed that many of the programs used by vista and xp are compatible with Window 7. Window7 has low level code, so after changing operating system of computer, the existing driver will search for the operating system parts which they were previously using, but they are not there. Due to which they can’t function. Install new drivers for them. This problem mostly occurs when we are changing from xp to window7.