You may have seen it die or forgot to partition and format it. Which is something Windows 98 doesn't do.
My Win98SE OS does not show my Primary IDE Slave drive when I select MY Computer.
The slave HDD is jumpered as slave and is able to be exercised using PC Technician (diagnostic program).
This is a Maxtor 71000A HDD which I can select via Device Managers Tools tab.
The Selection comes back with .... "This device is already installed, but it has been removed from the Hardware Profile. To add the device to this hardware profile. click finish".
The system searches for new devices but does not add the HDD to the Device Manager.
I have re-installed Win98SE to no avail.
I would welcome any ideas.