[alex]

The Blue Screen of Death, or more accurately the Windows stop message occurs when Windows detects an error from which it cannot recover. It stops what it's doing diagnostic information is displayed on a blue screen.

In XP, the contents of the PC's memory are dumped to a file that you can analyse later.

All XP stop errors are numbered according to the circumstances that caused the error, this helps a lot when troubleshooting them.



The screen above is a typical XP stop message. If you break it down into sections it does give some clues as to the cause of the problem(s) as to what caused its appearance. Reading a BSOD is not something you do everyday, but hopefully this article will enlighten you.



The bugcheck information shows the number of the stop error (in a hexadecimal format), information on why the system has stopped and the (text format) name for the stop error, in this case DRIVER_IRQI_NOT_LESS_OR_EQUAL.



The second section, recommended user action is rather generic and contains advice for you on possible troubleshooting steps.

This tends to be the same for just about every stop error, though the main advice try restarting your computer is the best possible first step to take.



The third section driver information may contain important information. If a driver file for an item of hardware or software is listed here it could be the cause of the BSOD. This can give you a heads up in the case of a reoccurring error.



The final part of the stop error screen is the debug port and status information section.

XP will attempt to dump the contents of system memory either to a file on the hard drive or to one of the COM ports in the case of a stop error. This section shows information about the procedure.

Next up we look at what causes BSODs in the first place, and how to fix them!

BSOD Causes?
In XP, stop messages usually take one of five forms:

1. Software errors during Windows operation. Software or device drivers installed in your computer may have errors or problems which cause a stop error, either constantly or under certain conditions.

2. Hardware errors during Windows operation. If a hardware device malfunctions or is removed during the operation of Windows, or if your hardware does not fully support the operations that XP expects it to support, a hardware stop error will occur. Outdated BIOS information on older computers might also be an issue.

3. Installation errors. The Windows XP installation process is the most sensitive time for hardware and disk errors. If there is a problem with your computer's hardware configuration or the media you are using to install XP, a stop error will likely occur.

4. Startup errors. Corrupted system files, hardware and driver errors can all cause Windows XP to halt with a stop message without correctly booting into Windows. An error of this sort will almost always require troubleshooting before Windows can be loaded correctly.

5. Intermittent errors. The most annoying and frustrating type of stop message, these crop up consistently but apparently randomly. These are usually cause by:

Defective Ram
Overheating cpu
Dead or faulty hdd
Faulty software or hardware drivers.

What can you do about them?
Unfortunately, Windows being Windows can crash in many weird and wonderful ways. I say this to qualify my next statement.

This article is really a general one of 'how to' as there's a huge range of possible causes of a BSOD.

Due to this there isn't really any clean cut way of coming up with an exact set of instructions to resolve the matter.

Given the range of possible crashes and stop errors, it's difficult to come up with a precise set of instructions for every possible BSOD.

Basics Below:

Basic troubleshooting for BSOD errors

First, log all relevant information when you see a BSOD flash across the screen. This includes the error number and friendly name from the bugcheck section of the BSOD (detailed above), and any file names specified in the driver information section (Also see above)

If the BSOD comes up on the screen for a split-second before the PC restarts and wipes all the useful information away, you'll need to change some settings within XP. In most cases, it should be possible to stop your PC from automatically restarting when it develops a major error, allowing you enough time to log the BSOD error message on some paper.

Right click on my computer > Properties > Select the 'Advanced' tab > and under startup and recovery click the settings button. Under the System Failure heading, untick Automatically restart.

Try to restart the computer normally into Windows. If the BSOD occurred while booting Windows, you may be taken to a troubleshooting menu and will have to select attempt to start Windows normally. If your computer starts correctly, continue using it (and log the error information for reference).

If the BSOD reoccurs at random or irregular periods, see Part 4 on resolving intermittent stop errors.

If your system does not start correctly or the stop message happens again, reboot the system. When the POST (memory checking) screen comes up, press F8 repeatedly. This will bring you to the Windows advanced options menu.

In the Windows advanced options menu choose safe mode to attempt to boot into Safe Mode. Safe mode loads XP with a minimal set of drivers and no software that is in your start up list (AV software etc). If faulty software or drivers are causing the BSOD, safe mode should load correctly. If safe mode loads correctly, refer to Part 1 on

Troubleshooting software stop messages.
If safe mode doesn't load correctly, and/or you get the same stop message upon trying to load safe mode, then it's at thsi point you should try: Restore last known good configuration option in the advanced options menu.

Restart your computer, pressing F8 again to load the advanced options menu and click: Last known good configuration (This is the pc's most recent setup, that worked). This uses XP's built-in system restore utility to restore the most recent save point, )which should be the last time you installed any drivers or other software). If your system boots normally after this, then hopefully your problem has been fixed.

If you are still seeing a BSOD after performing the steps above, or if system restore was disabled on your system, note down any new information on the error and ask yourself:

Have I installed any new hardware or software just prior to this problem occurring? The driver information section of the BSOD may help with this.

(If you did install new hardware or software, this can give you a head start in fixing the problem).

If not, scroll down to the advanced troubleshooting sections below. As its more than likely the BSOD is going to take more time to resolve.

Specfic Repair Instructions
If you have a reoccurring Blue Screen Of Death or crashing problem, and can't use Windows fully, or at all, because of it, it's time to look at more specific methods of troubleshooting. Depending on the results of the basic troubleshooting steps above, you should have a good idea of whether the problem that is causing the stop messages is related to software or drivers you have installed, or is a hardware or system file issue.

Basically, if you can't boot into XP safe mode because of crashes or BSOD, it's likely you either have a hardware error or one or more essential system files is corrupt or not-resident within XP. If you can boot into XP safe mode, but get constant or frequent BSOD's when running XP normally, you have a software or device driver problem.

Part 1: Troubleshooting Software & Driver stop messages
Assuming you can boot into safe mode, the first thing you should attempt to do is perform a virus and spyware scan of your system, (if you have the software utilities)

If anything is found and removed in either scan, attempt to restart Windows XP normally.

If this doesn't help, boot the pc back into safe mode. The next step is to use the built in system restore utility to (fingers crossed) return XP to working order. When run in safe mode, you can access all recent restore points created by the system restore utility. This gives you more choice than the last known good configuration command in the boot menu which only restores the most recent one.

To use the system restore utility, go to start > all programs > accessories > system tools > system restore.



The utility reserves hard disk space and creates a restore point each time you install or remove software. If you are fairly sure you know what you installed that might have caused the problem. Restore the point created at that date. (Note:Any software installed since then will cease to function, as links created to it in the registry will be removed). Otherwise, restore your system to the most recent point created before you started having BSOD troubles. If the first one does not succeed in curing the problem, try the next most recent, and so on.

If system restore has been disabled on your system, or if the utility did not fix your problem, it's time to try more specific cures.
Did you install new software or device drivers before the problem occurred? If so, you need to disable them as they are probably the cause. Drivers need to be disabled or rolled back, and software needs to be uninstalled or be stopped from running automatically.

Fixing device drivers
In the case of a device driver, you can either roll it back to a previous version of the driver or disable it. To do either right click on my computer, click properties, click the hardware tab and select device manager.

Once here, expand the section where the faulty device driver is located (Graphics card drivers are found in display adaptors, sound card in sound video and game controllers and motherboard drivers in IDE/ATAPI controllers). Highlight the device, right click and select properties. Go to the drivers tab now.

Within the drivers tab you can use the roll back option to revert to the previous driver version, or use the uninstall option to remove the driver completely. (Note: You shouldn't uninstall graphics card or motherboard drivers, as this will stop XP from booting just as effectively as your BSOD problem is doing. Attempt to 'roll back' the drivers first).

A second possibility is to right click on the faulty device in device manager and click disable which will force XP not to load that device driver during startup. For obvious reasons, you should not use this on video card or motherboard drivers either.

If you are able to boot into Windows normally after this, look for a working driver to update any device that you uninstalled or disabled.

Fixing software problems
If the BSOD is being caused by a faulty or incompatible program that starts automatically when you boot Windows, causing a crash, there are a couple of easy ways to prevent this.

The quickest, easiest and best way is to use Sysinternal's autoruns program to display all auto-running sodtware on your pc. You can then pick through them and disable any potential causes.
To do this go have a look here: www.microsoft.com/technet/sysinternals/utilities/Autoruns.mspx




This program displays all software (including various essential Windows files) that runs automatically after XP loads. By unticking the boxes, you can disable specific programs and prevent them from loading. (Note there are several entries here you should not disable at any time, the two most important of which are userinit.exe and explorer.exe. Be extremely careful with anything authored by Microsoft in this list (though it is possible for malicious startup programs such as spyware and Trojan horse viruses to use the Microsoft label here also).

If you can't get access to autoruns, you can still use the built-in MSCONFIG utility to edit startup programs. Go to start > run > and type 'msconfig'. Then click the startup tab.




While this utility's display is not as detailed as that of autoruns, it has the advantage of not displaying any critical system files. This way you can untick any or all items on this list without fear of messing up Windows even more.

Once you have used either utility to edit your startup programs, reboot normally into Windows.

Part 2: Troubleshooting hardware and system file based BSODs
If you can't even boot into safe mode without a stop message, and the last known good configuration boot option didn't help, it's likely you have a hardware or system file error. There's a procedure for each and neither is particularly fast, so the troubleshooting steps are listed below in ascending order (easiest first).

Checking for hardware errors
Firstly, have you added any new hardware devices or peripherals to your system recently? If so, power down the pc and remove them, then attempt to boot again normally.

If you changed the motherboard in your pc, or moved your Windows installation to a new system before the error occurred, you must perform a Repair Install before XP will work correctly again. See the section below entitled Fixing missing or corrupted system files.

If you haven't added new devices recently, or if removing them does not solve the problem, it's time to test your ram

Testing system memory
Obtain the Windows memory diagnostic or Memtest memory diagnostic programs, then use them to boot your system and test the ram. If either of these programs shows any errors in your memory, you've likely found the cause of the problem and the chances are you'll need to purchase new ram.

Fixing missing or corrupted system files
XP will often refuse to work if certain system files are missing or have become corrupted through hard drive or virus issues. Also, changing the motherboard (or the entire system) under your XP installation will stop it working until the system files are repaired and updated.

To do this, you should perform a Repair Install.
The repair install reinstalls all Windows system files while leaving directories, settings and user data intact. This should fix any corrupted files that are causing BSODs and crash issues. To perform a repair install:

1. Boot from the XP installation disc
2. Select the press enter to set up Windows XP now option
3. Press F8 to skip through the EULA (End User Licence Agreement)
4. Select R to begin a repair installation

Your system will go through the entire XP install process, but won't attempt to replace any of your existing data. It will purely reinstall the system files and redetect all hardware. Once the process has completed, your computer will reboot. (Note: If you perform a repair install, you will need to visit the Windows Update Site and reload any patches and Service Packs that you previously applied to your system, as the repair install will remove them all).

Identifying other defective hardware
If you are still experiencing crashing, power down your pc again, open the case and remove all non-essential hardware. The only things still connected to the system and motherboard should be:

Mouse & keyboard
Hard drive
Optical drive
Video card
Ram
CPU
PSU

(If you've more than one of any of the above, remove also)

Now try booting the computer into safe mode first, then normally. If you can boot into Windows without experiencing a BSOD, you can be confident the issue is with one of the peripherals you removed. Now you can pinpoint the problem by selectively reinstalling each component (with the power off) and restarting Windows.

Part 3: Troubleshooting Windows XP install BSODs
Constant Blue screen errors while attempting to install Xp are usually caused by hardware or media problems. The most common hardware-related installation issue is faulty ram, which can cause hell with any XP installation. Overheating or a dead or faulty hard disk are also common causes. A severely scratched or otherwise faulty XP install CD may also cause stop errors.

First, check the XP disc and clean or replace it. The next step should be to test your Ram for errors with a diagnostic program (see above).

Now it's time to test the hard drive for errors. Visit the website of your hard drive's manufacturer and download their drive diagnostic utility software. Every major hard drive company makes a utility like this freely available. Follow the included instructions to install the software and test your drive(s) for errors.

If no errors were found in memory or with the hard disk, you need to ensure that your processor is not overheating. Make sure the fan on the heatsink is in working order and reboot the computer, pressing DEL repeatedly on startup to go into the BIOS setup screen.

Let your PC run on this screen for an hour or so, checking back to make sure it has not crashed. If a PC crashes on the BIOS screen, it usually means the processor is overheating for one reason or another.

Part 4: Troubleshooting Intermittent BSOD's or Crashes
First step: Boot into Safe Mode and try to use the system as normally as Safe Mode allows. If the errors don't occur, it's likely to be software or drivers that are causing the problem. (See Part 1 on treating these).

If the errors occur randomly, even in safe mode, hardware issues are likely to be the cause. (See Part 2 on treating these).

Also you should check that the processor heatsink fan is working correctly, and that your PC is not overheating.

That's it, hope it's helpful.

[NobleGeek]

awesome tut on bsod ! thanx !! one of the finest, if i may say so !

[alex]

Thanks very much! appreciated. :)