That bit version means a lot. When Windows 7 was initially released, there were plenty of threads concerning this. Many users were simply bashing 64 bit because a 10 year old printer (usually Canon) would work with Win 7 32 bit, but not 64 bit. Some hardware companies do release both 32 & 64 bit drivers for their devices, but most these devices were made in recent years.
Simply speaking, many hardware companies don't provide driver support after a few years. And many devices that were made for XP usage has no 64 bit drivers available. The device may say "XP & up", but it depends on when it was made.
Cat