Need Help with error code 0x005F0013+0x00600002

Acronis True Image Home 2012 was working flawlessly until now. Suddenly, just before it's ready to start the re-boot process, I get this error message...

"Failed to activate Acronis bootable agent" -- "Disk doesn't have BIOS number"

Error Message # 0x005F0013+0x00600002

I've never seen this before, and have no idea how to correct it.

Cannot get any information on the error code.

I would appreciate any help I can get...thanks!