CASE HISTORY #2
       by The Disk Doctor



THE STORIES YOU ARE ABOUT TO READ ARE
TRUE.  THE NAMES HAVE BEEN DISGUISED TO
PROTECT THE INNOCENT.....


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Copyright (C) 1987,  the Disk Doctor.

First published in the Rochester (PC)^3 News:
   Picture City PC Programming Club
   PO BOX 20342
   Rochester, NY 14602
The Disk Doctor may be contacted at this
address, or via CIS [73147,414].

This material may be reproduced for internal
use by other not-for-profit groups, provided
this copyright notice is included.
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9:15am
I was indexing a database application when
I heard a faint knock at my door.  "I'm
looking for the Disk Doctor," I heard her
say as I turned towards the door.
 
"What can I do to help you?" I asked,
gesturing her to come into my office.
 
"I was working on my word-processor, and
when I went to save my work, the computer
won't accept it," she explained.
 
"What do you mean?  Won't accept it?"
 
"It says Disk Write error."
 
"I see.  Where's your disk?"
 
"Right here."  She pulled both the data
disk and a MultiMate disk from her purse.
"Are you a hacker or something?"
 
I jumped to my feet.  "You do me a
grave disservice, madam.  I am the
Disk Doctor.  I have taken an oath to
use my skills only to assist the
misfortunate and educate the helpless.
Don't ever use that degrading term in
presence again."
 
"Okay, okay. I don't care what you call
yourself.  Can you help me or not?"
 
"Let's see what we have here."
 
 
 
9:18am
I did a DIRectory on the both disks,
no problem.  Next, a CHKDSK - still no
errors.  I created a little scratch file
on her disk using 'COPY CON TEST.TXT', and
that worked okay, too.  "Where did you get
this disk?" I asked.
 
"My friend W. formatted it for me.  My
other document disk was filled, and I was
in the middle of Multimate, so I couldn't
format a disk without losing all my work."
 
I had a hunch.  "W. has an IBM XT
computer, right?  With a 10 mega-byte hard
disk?"
 
"Yes, that's right..."
 
"Let me look at your Multimate disk
again."  With DEBUG, I peeked at the first
sector of COMMAND.COM for the copyright
label.  I had been looking for an error on
each disk, whereas the problem was between
disks.
 
 
9:21am
"This disk contains the DOS 1.1
operating system.  DOS 1.1 can only read
disks formatted with 8 sectors per track.
I know W. must be running DOS 2.0 or
higher, because you need that operating
system for a hard drive.  But the newer
version of DOS formats floppy disks with 9
sectors per track."
 
"Are you saying that the two disks are not
compatible?  But I've used W.'s computer
many times to print some of my files..."
 
"The different versions of DOS are `upward
compatible'.  That means you can read and
write to a 8-sectored disk with DOS 2.0,
and not even realize the difference.  But
you can't use a 9-sectored disk with
DOS 1.1."
 
"How can you tell which is which, then?"
 
"The easiest way to check the disk format
is with the DOS command CHKDSK, which is
on your DOS diskette.  CHKDSK displays the
total disk space.  There are 320,000 bytes
on a 8-sectored disk, and 360,000 on a 9-
sectored disk."
 
"Maybe I should upgrade my DOS, too?"
 
"It wouldn't be a bad idea to upgrade.
The newer versions of DOS give you 12%
more disk space, plus several new and
improved commands."
 
"What do I do?  Just call up IBM and order
DOS 2.0?"
 
"Well, you can't order IBM DOS 2.0
anymore.  The latest version is now
DOS 3.2.  The best thing would be to find
a dealer who still has a copy of DOS 2.0
or 2.1."
 
"Oh, I see.  I don't want to be
incompatible with W.'s DOS 2.0, right?"
 
"No, that's not a problem anymore.  All
the newer versions of DOS will format your
diskette the same way.  But DOS 3.2 has a
lot of features that you won't use at this
point:  support for 3-1/2" drives, network
support, and so on.  The main thing I
recommended DOS 2.1 is because DOS 3.0 is
so much larger, it occupies more space on
your floppy disk."
 
 
 
9:25am
As we talked, I had copied all her
documents on to my RAM disk.  "Why don't I
reformat this disk right now, so you can
use it in the meantime."
 
"I don't understand.  You have an XT,
so you must be  running DOS 2.0 or higher.
How can you format a disk for me?"
 
"The newer DOS versions give me the option
of formatting with 8-sectors.  I just put
the `/8' parameter on the FORMAT command.
Trust me."
 
She laughed, "Okay, you're the doctor."