Got error when trying to format the new D: drive :(

Ok, I partitioned the drive as you said, and made the partition the maximum available space.
Fdisk went through it's testing and partitioning and all seemed well. The it said it
was done and to hit escape to go back to the main menu, I did that, then hit
escape again to leave Fdisk, the it gave me a message saying I had to reboot
before I could format the drive and that a letter had been assigned to the drive.
So far, so good. So I rebooted with the boot disk again and typed "format D:"

I then got this message
format not supported on drive D:
format terminated

huh??

I went to D: at the DOS prompt and did a DIR. And I could see some files there,
just basic dos files. Does making a Primary DOS partition place basic DOS
files on the partition on the new partition?

I went into Win98SE and I could see the new D: drive letter now, but
I can't access it from there.
I don't know why it won't let me format the D: drive.

Any ideas?