Nokia Alfaskop TT/386 User Manual page 85

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BIOS (63) : Hard disk <d> error, status = <xx>
BIOS failed to read a sector on the innermost cylinder of drive <d>.
Status <xx> is the return code from the last "Verify sector"
(function 04) command issued by BIOS. Possible codes are listed
under BIOS interrupt 13H. Most probable reason for this error is a
wrong hard-disk type in the CMOS memory. Run the Setup program
and set the correct type. If the error still persists, then the whole
innermost track is bad and the hard disk must be replaced.
BIOS (70): Boot load failed. System stopped.
An interrupt 18H was issued, indicating boot load problem.
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