After replacing a CMOS battery on a seven year old computer, running Windows 8.1, I started getting the above error message. I first was concerned that my hard drive was fried, but the computer seemed to boot correctly and run without any problems.
The problem seems to be that when the message says “Diskette” they literally mean an old-style 3.5″disk drive. Somehow that drive is not working correctly and that’s the reason I’m getting this message.
The way I finally solved this was when I got the message I chose F2 and selected the “Standard Cmos Features.” I then selected Drive A at the bottom and changed the setting to None. Now my computer runs like a champ.