I see settings for 24 bit in Vegas, Sound Forge, and Acid but can't use it. Get message that says Microsoft SoundMapper doesn't support 24 bit. Try to do it with SoundBlaster Live! and that won't work either. Using Windows 98SE. Do you need latest OS and Soundcards?
Yes, the hardware and the drivers for the hardware must support 24 bit.
There are altenative drivers for the SBLive! on Creatives Web site. They are the WDM drivers. While the SBLive can't actually do 24 bit audio, these drivers will permit a project to be at 24 bit. However, there is not much point in this, since the output will be dithered down to 16 bit.
So, if you need 24 bit and want to actually hear 24 bit, then you will need to get another card.