Hard Disk Troubleshooting


Eventually, if you work with computers long enough, you are going to 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 everythingand 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.


These sections are not meant to be comprehensive. Full books have been written on solving hardware problems, and thousands of individual chapters on hard drives and the multitude of problems they can exhibit. What these sections will do, however, is give you some tried-and-true directions to head in if your hard drive starts to give you grief.

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 sizesbe 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 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 operating systems when the problem is not software at all, but a failing CMOS battery 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 or her 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 problemor what you think is a hard drive problembefore you pick up a CD-ROM 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 operating system uses these structures to tell programs where their data is located. When you have inconsistencies, one of two forces is at work:

  • You're not seeing or you're overlooking something.

  • You could have more than one problem on your hands.

The key of 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.

So, the next highly recommended tools to pick up, after you've pondered and had a cup of coffee, 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

  • File structure

Hardware-related problems involve the hard drive itself, cabling, power, connections, and the motherboard.

File structure problems involve the tracks and partitions on the hard disk, the boot records, and the files the operating system 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. 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, at times, overlap. For example, a damaged master boot record (MBR) may be the result of a failing hard drive; repairing the MBR might fix a consequence of the problem but not the problem itself.

SCSI Disk Boot Problems

A boot problem can sometimes be caused by SCSI settings that have changed since you installed Windows XP. The state of the SCSI BIOS at the time you installed Windows XP becomes part of the setup of the operating system and is stored in the BOOT.INI file. If you subsequently make a change in the SCSI BIOS after NT is installed, that alone can contradict the stored BOOT.INI file settings and can prevent the operating system from finding the system files and booting up. Don't change the SCSI BIOS settings after you install Windows XP, or if you do, you should edit BOOT.INI in a text editor (carefully!) to reflect the changes. The BOOT.INI file uses the following syntax:

 scsi(A)disk(B)rdiskpartition\<winnt_dir> 

Here are the specifics for the parameters in the ARC path when you use the scsi() syntax on an X86 computer:

  • A is the ordinal number for the adapter linked to the Ntbootdd.sys driver.

  • B is the SCSI ID for the target disk.

  • C is always 0 when SCSI drives are used.

  • D is the partition.

When an IDE ATA drive is in use, this line will have multi(A) as its front item. Then, B remains 0 and C indicates the drive used.

Take note that A, B, and C are all ordinal numbers; that means you should start counting with zero. So, the second drive is 1, the third is 2, and so on. But, D is a cardinal number, so the first partition is 1, the second is 2, and so on.


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. Just follow these steps:

1.

Turn off the computer, open it, and check the cables. Are the power and data cables attached to the drive? Is the wide, flat data cable flipped over backward on end? Check to see that pin #1 on the motherboard connects to pin #1 on the drive.

2.

Check the settings on the drive to make sure they are correct. If you have a SCSI drive, check the ID number and termination as per the instruction manual for the drive. If you have an IDE drive, check the master/slave settings and channel assignment. If you have two devices on the same 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 IDE channel. You typically change the setting by using a little jumper on the back of the hard drive next to the data and power connectors (ditto for IDE-based CD-ROM drives).

3.

Check the BIOS settings by pressing the appropriate key during POST (Power-On Self Test) and having the computer autodetect the drive type. Make sure the drive is listed and/or recognized.

TIP

Most modern PCs and BIOSes autodetect the hard drive that's connected to the data cable after the drive gets power. You no longer have to enter all the explicit information about the drive, such as number of heads, sectors, the landing zone, and so on. Just set the BIOS to Autodetect.


Hard Drive Initializes But Will Not Boot

Windows XP offers several features that allow you to repair a system that will not start or will not load Windows XP. These features are useful if some of your system files become corrupted 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 rather than hard drivespecific problems. If you've already tried the actions listed in this section to no avail, flip over to Chapter 33, for details on numerous other recovery techniques that may be of benefit to you. Be sure to check out Safe Mode, Recovery Console, and parallel installations.



Special Edition Using Microsoft Windows XP Professional
Special Edition Using Microsoft Windows XP Professional (3rd Edition)
ISBN: 0789732807
EAN: 2147483647
Year: 2003
Pages: 450

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