Sata

I’ve mentioned this one a couple of times so I’ll give a bit more detail because it is a nightmare to solve if you don’t know what is going on. If you have both a parallel ATA (PATA, this is the way most hard drives were connected on desktops and laptops until around 18 months ago) and a serial ATA (SATA) hard disk controller on your PC (as many do) and hard drives connected to both controllers, you are going to get hit by the GRUB PATA/SATA bug.