If you work with computers long enough, you will face some form of hard disk problem. It’s not a matter of if; it’s a matter of when.
The laws of statistics apply to everyone and everything—and that
includes hard drives. In the following sections, when I speak of hard
drive problems, I’m not referring to a software program that is acting
petulantly or a DLL that has been overwritten by a poorly designed
installation routine. I’m talking about the inability to access a
critical file, a hard drive that will not boot, or one of those cryptic
“Fatal Error—Cannot access hard disk” messages that cause the blood to
drain from the face of even the hardiest administrator.
Hard
drive problems range from file system structures that have been twisted
out of shape to catastrophic, dead-in-the-water hard drive failures.
And as any seasoned administrator will tell you, the catastrophic
failures are the easy ones to diagnose and fix. More often than not,
the inconsistent “What the heck?” problems are the real
“head-scratchers.”
To keep it simple, let’s
begin with the most important factor in troubleshooting problems of all
shapes and sizes—be it a car that will not start or a computer that
will not boot. And that is....
Take the Mental Approach First
I
come from a long line of tradesmen who made a living getting their
hands dirty and solving mechanical problems. As a writer and computer
consultant, I rarely get my hands dirty anymore, but I have discovered
that the principles of problem solving that I learned when I was young
are the same across all fields. You need to be methodical, and if you
are going to make assumptions, they had better be good ones; otherwise,
you just might steer yourself down the wrong garden path.
The
very first step to take when you have a disk access problem is to stop,
sit down, and think. Although this advice might seem obvious, it is
seldom realized in practice. People experience what they conclude is a
hard drive problem, open their case, and start ripping out components
when, in fact, they have a file system problem that could have been
easily resolved by running Error Checking on their drive. Similarly,
others start reinstalling OSs when the problem is not software, but a
failing CMOS battery or a loose cable that is causing the motherboard
to lose sight of the hard drive.
None of
this exposition is meant to imply that I’m smarter or better at
diagnosing problems than the next guy, and in the end, I might come to
the same conclusion as the person who leapt in and started ripping his
case apart. What separates us, in my humble opinion, is that the steps
I use to solve a problem today will apply equally well to a completely
different problem I encounter a week from now.
So
when you have a hard drive problem—or what you think is a hard drive
problem—before you pick up a DVD or a screwdriver, get yourself a cup
of coffee and take a few minutes to get a clear picture of the nature
of the problem in front of you. The following are some questions you
might want to ask yourself:
When did the problem start?
What was I doing when I first noticed the problem?
Is the problem consistent? If so, how? If not, what is missing from the puzzle?
This
last point bears some elaboration. Computers, as a whole, are
extraordinarily consistent devices. Input goes in here; output comes
out over there. In the case of hard drives, you lay out structures on
them, and the OS uses these structures to tell programs where their
data is located. When you have inconsistencies, one of two forces is at
work:
The
key to this forced reflection is to have a “plan” before you react. And
the cornerstone of that plan must be to do no further harm, and to
figure out what the problem is without complicating matters further.
After
you’ve pondered and had a cup of coffee, the next highly recommended
tools to pick up are a notepad and a pencil. Begin by jotting down some
notes on what happened, what you think the problem is, and what might
be a good course of action to solve that problem. Use your notepad to
reason out the problem; more often than not, eliminating a piece of
flawed logic with an eraser is easier than restoring all the programs
to your hard drive.
Problems and Solutions
Hard drive problems fall into two general categories:
Hardware-related problems involve the hard drive itself, cabling, power, connections, or the motherboard.
File
structure problems involve the tracks and partitions on the hard disk,
the boot records, or the files the OS uses to initialize itself.
If
you power up your computer and the BIOS cannot find the attached hard
drive, chances are, you have a hardware problem. On the other hand, if
the BIOS finds and recognizes your hard drive but fails to boot, you
likely have a file structure problem. Note the “chances are” and
“likely” qualifiers in these sentences. As you read through the
following scenarios, bear in mind the complications that can be brought
on by compounded problems. In other words, file structure problems and
hardware problems can sometimes overlap. For example, a damaged master
boot record (MBR) might be the result of a failing hard drive;
repairing the MBR might fix a consequence of the problem, but not the
problem itself.
System Starts but Cannot Find the Hard Drive
If
the computer fires up (the BIOS information appears and the floppy
drive is accessed, but nothing more), you have some sleuthing to do.
Follow these steps:
1. | Turn
off the computer, open it, and check the cables. Are the power and data
cables attached to the drive? On SATA drives, be sure the SATA data and
power cables are firmly attached to the drive. First-generation SATA
drives don’t use locking mechanisms on these cables, and they can be
easily removed. If you recently installed a new piece of hardware or
were mucking around inside your computer case, it’s very possible that
you unintentionally jiggled a connection loose. If you use an ATA/IDE
drive, be sure pin 1 (marked as a red or speckled stripe on the edge of
the cable) is lined up with pin 1 on the hard disk and motherboard. If
you use only 80-wire cables, the cable is keyed, so it can’t be
installed wrong. However, older, 40-wire cables (often used on CD and
DVD drives) are not always keyed.
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2. | Check
the settings on the drive to be sure they are correct. If you have a
SCSI drive, check the ID number and termination, per the instruction
manual for the drive. If you have an ATA/IDE drive, check the
master/slave settings and channel assignment. If you have two devices
on the same ATA/IDE channel, both set to master or both set to slave,
there will be a conflict. You can have only one master and one slave
per ATA/IDE channel. You typically change the setting by using a little
jumper block on the back of the hard drive, next to the data and power
connectors (ditto for ATA/IDE-based DVD drives). Many recent systems
use the CSEL or Cable Select setting for both drives. When used with an
80-wire 40-pin cable, the blue end of the cable plugs into the
motherboard, the drive on the middle of the cable (gray connector) is
slave, and the drive on the far end of the cable (black connector) is
master. Note that many Western Digital hard disks do not use a jumper
block if they are the only drive on the cable.
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3. | Check
the BIOS settings by pressing the appropriate key during POST (Power-On
Self Test) and having the computer autodetect the drive type. Be sure
the drive is listed and recognized. If you have just upgraded to SATA
hard disks, be sure the SATA host adapters on the motherboard are
enabled in the system BIOS. On many systems, SATA functions are
disabled by default. If you use an SATA host adapter card, or if the
SATA ports on your motherboard use a third-party chip rather than being
controlled by the motherboard chipset, you will need to install the
appropriate third-party driver file before you can use SATA drives.
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Tip
Most
modern PCs and BIOSs autodetect the hard drive that’s connected to the
data cable after the drive gets power. You no longer need to enter all
the explicit information about the drive, such as the number of heads,
the sectors, the landing zone, and so on. Just set the BIOS to
Autodetect. |
Hard Drive Initializes but Will Not Boot
Windows
7 makes it easier than ever to repair a system that will not start or
will not load Windows 7. These features are useful if some of your
system files become corrupt or are accidentally erased, or if you have
installed software or device drivers that cause your system to not work
properly. However, these features are used more to restore a system
with a damaged Registry or destroyed system files than to resolve hard
drive–specific problems.
Windows 7 doesn’t use the boot.ini
file familiar from Windows NT, Windows 2000, and Windows XP
installations. Instead, Windows 7 uses the method of determining boot
settings known as a boot configuration database (BCD) store. BCD is
compatible with both traditional BIOS firmware and the new Extensible
Firmware Interface (EFI). EFI firmware will eventually replace BIOS
firmware in new systems and also supports dual-boot installations with
older Windows versions. You can make simple changes to the boot
sequence (such as specifying whether Windows 7 or an older version of
Windows is the default OS) with the System Configuration tool MSConfig . However, you can also use the command-line bcdedit tool to edit the boot configuration, with Administrator permissions.
