Looking at this from 15K meters... hopefully you're not trying to get drive or volume serial numbers for the purpose of copy protection.

I think in another branch/thread you said these machines where you're trying to get drive or volume serial numbers are running virtualized.

When virtualized, you don't get a physical hard drive (you get a VHD file instead), you get whatever the VM decides to give you. I don't know the specifics for VMWare but that value could well be the same for all VMWare VMs.

Even when you're running on dedicated hardware there will be problems getting drive serial numbers. For example, my dev machine has 2 drives in hardware RAID1. Which one will be returned by a drive serial number function? Since February, when I built this machine I've had both drives fail (at different times) so neither drive serial number is the same as at the start. I'd be annoyed if software stopped working because of this.

You might have better luck with a volume serial number, which I believe gets generated by Windows when the OS is installed. However, both this and the drive serial number can easily be duplicated if you simply copy the VM, and run it again on the same, or separate hardware.

You could look into network adapter MAC addresses or other similar hardware parameters but they all have that same problem when virtualized.

One thing that can help in some environments is just to use the machine's NetBIOS name. That must be unique on a locally routable LAN. It's something that's a PITA to change (especially for servers) and tends to stay the same regardless of hardware changes/upgrades/replacements.