Hi, can you give me a bit more detail than "preparing auto repair"? Perhaps you could type in the COMPLETE diagnostic message, and I can, first off, determine whether this is anomalous or a poorly-worded, but routine, announcement.
You say you just bought this? And from where?
Well he was a liar, evidently.
Did you see the machine boot Windows and behave properly BEFORE you bought it? Think of it like buying a used car. "It runs smoothly"--yes after they stuff bananas in the transmission to hide the rattling.
What's even more of a concern is if it boots SOMETIMES, that could be as trivial as loose cabling, but it sounds more like a shaky disk controller that is able to fetch the MBR sometimes but not at other times.
Do you have an emergency boot device (often, there's a USB flash drive you can boot from) and have you tried it? WARNING: never buy a used system without all the pieces (installation disks, emergency recover disks, etc.).
And should I assume this wasn't terribly expensive, like, maybe $50?
I don't want to disappoint you or impugn your friend of thirty-five years, but he seems to have sold you something very, very questionable indeed. Do you need suggestions on how to get your money back without going through gyrations or imperiling a long-standing relationship?
O.K. Sorry for your experience. Now, you COULD keep it and deal with it booting SOMETIMES, but do you need the headache? Also, if the disk controller is that shaky, it's going to get worse, not better, over time. Best of luck.