When trying to install Windows 7 to dualboot with Snow Leopard on an existing partition on a Dell Mini 10v, I kept getting this error:

“Setup was unable to create a new system partition or locate an existing system partition.”

No matter how many times I deleted, created, and reformatted the partition using Windows’ installer or OS X’s disk utility, Windows 7 said it could not install to Partition 0.

I also got the error “Windows cannot install to a GPT partition”, and when I tried converting it to MBR in Diskpart, the error “Cannot convert partition”.

The solution was really, really, really stupid:

In my BIOS, I had my boot order set as USB drive before hard drive so I could boot from it. Apparently, that confused the installer. I set the hard drive as the first boot device, and then selected to boot from USB by hitting F12 when the POST screen appeared.

Windows is almost 30 years old, and it still has these types of problems? Really, Microsoft?