Question : Problem: will overheated processor cuase error message "operating system not found" half way thru the day

I get the error after the laptop has been running for a while.  And once it warms up and the error starts it is continuous.  After so long it wont even reboot it just errors out.  I thought it was the hard drive but now that it is open, I see the heat sink fan NEVER spins.  Suggestions Please

Answer : Problem: will overheated processor cuase error message "operating system not found" half way thru the day

If the heat sink fan doesn't spin, all kinds of errors are possible, including the one you listed.  From your description, there is definitely an overheating problem, so my suggestion is that you check for a loose fan wire, an incorrect setting in the BIOS (choose default fan settings), or replace the fan entirely.