Slave drive set up

I’m attempting to slave a second hard drive into my machine.
Here’s what I have done:
– set the jumpers on both drives properly
– set the CMOS to Auto detect for the second drive

Here’s what’s happening:
– BIOS recognizes both drives, lists them both at start up
– Windows (98) doesn’t see drive, and so I can’t use it.

What am I doing wrong?