Do 64-bit operating systems support 32-bit software?

* A 64-bit computer can run a 64-bit operating system, naturally

* A 64-bit computer with a 64-bit OS can run 64-bit programs

* A 64-bit computer can also run a 32-bit OS

* With either a 32-bit or a 64-bit OS, a 64-bit computer can run almost all 32-bit programs

* A 64-bit computer with a 64-bit OS cannot run old 16-bit programs

You will probably find the occasional 32-bit program that has a compatibility problem with 64-bit Windows. Often you can get around this problem by running the application in a 32-bit OS inside of Microsoft Virtual PC.

Much more commonly, though, you'll find that older printers and other peripherals don't have 64-bit drivers. It really doesn't pay for the printer vendor to spend time and money creating a 64-bit driver for a model they're no longer selling. A virtual PC won't help you here. If there's no 64-bit driver you just can't use that peripheral with a 64-bit operating system.