Apply the latest firmware update.

Check that your drive is truly not being detected by checking in Disk Manager. In some cases, Windows will not assign a logical drive letter to your hard drive. If this is the case you will need to image the drive on a physical level.

IDE
The latest firmware update has IDE detection enhancements.

Make sure your drive is configured as a standalone master device.

SCSI
The latest firmware update has SCSI detection enhancements.

If you're trying to connect without termination, try it with termination or vice versa.

Try and power the drive from an external power source. Some older drives needed substantial power to spin up.