Operating System not found appears when I switch on laptop Panasonic CF-27 Toughbook

On all Panasonic Toughbooks, if the hard drive
is missing because the HDD was removed or
destroyed by the previous owner, the you might
get this error message. Otherwise some companies
will simply "Wipe" the hard drive with a cleaning tool
and you will get the same error message.
If you are VERY unlucky then the hard drive might
also be damaged or corrupted but this is less likely
in a Panasonic Toughbook series.
There are tools on the HIREN Boot CD v15 which can
verify the "Health" of the Hard Disk Drive. The health
should be 100% if it is to be trustworthy.
Good Luck and Regards.
Richard - Montreal Based
Panasonic Canada Toughbook Authorized Dealer since 1989

You might have a corrupted/bad hard drive