i have a desktop with vista ultimate(32 bit) on it and want to upgrade it to 64 bit without losing all my files, programs, settings, etc. i have the retail version that came with both a 32bit disc and a 64 bit disc. is it possible to upgrade or would i have to do a clean install? i don't want to take any risks of losing my data and there is just too much to backup. also there is a virus on this desktop which is why i want to switch hoping that somehow it will get rid of it because i have used avg and windows defender but neither is able to remove it, they just keep on finding trojan files and bad cookies that the virus is creating. if anyone has any advice on how to remove the virus that would also be greatly appreciated!