10 Reasons Why PCs Crash And You Must Know

Fatal error: the system has become unstable or is busy," it says. "Enter to return to Windows or press Control-Alt-Delete to restart your computer. If you do this you will lose any unsaved information in all open applications."

You have just been struck by the Blue Screen of Death. Anyone who uses Mcft Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?

1 Hardware conflict

The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.

For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.

If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:

* Start-Settings-Control Panel-System-Device Manager.

Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.

Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).

When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.

To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip [this is quite hold article, I need to update some stuff here]. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.

2 Bad Ram

Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.

But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.

One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.

Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.

EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.

3 BIOS settings

Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.

Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.

Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).

4 Hard disk drives

After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to

* Start-Programs-Accessories-System Tools-Disk Defragmenter

This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.

The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).

Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to

* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.

Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.

Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to

* Start-Programs-Accessories-System Tools-ScanDisk

Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.

5 Fatal OE exceptions and VXD errors

Fatal OE exception errors and VXD errors are often caused by video card problems.

These can often be resolved easily by reducing the resolution of the video display. Go to

* Start-Settings-Control Panel-Display-Settings

Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.

If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to

* Start-Settings-Control Panel-System-Device Manager

Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.

If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.

The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.

Another useful way to resolve video problems is to go to

* Start-Settings-Control Panel-System-Performance-Graphics

Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).

Look up your video card's manufacturer on the internet and search for the most recent drivers for it.

6 Viruses

Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to

* Start-Settings-Control Panel-Add/Remove Programs

Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.

A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.

An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).

7 Printers

The action of sending a document to print creates a bigger file, often called a postscript file.

Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.

If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.

8 Software

A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.

The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.

Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org

Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.

Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.

Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.

Remember to restore all the BIOS settings back to their former settings following installation.

9 Overheating

Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.

One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com

CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.

10 Power supply problems

With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.

If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.

It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.

How To Hide & UNHIDE Hard disk Volumes By CMD Command

How To Hide and unhide the hard disk Volumes using CMD Commands :

    First check how many drives are there in my computer and then see which drive holds your secret files.Then make the drive to invisible by following the below steps of using cmd commands,

    start->run->cmd->DISKPART
    DISKPART>list volume (it list available partition volumes)
    select the volume by SELECT VOLUME 1or 2 ..
     Hide the selected volume by REMOVE LETTER C or D or... command.

Note :For Unhide the hidden drive use the command ASSIGN LETTER after selecting the hidden drive.


Now to unhide the partition:
Go to an elevated command prompt=run cmd.exe as administrator

Enter following commands:

DISKPART --- run the diskpart program
LIST DISK ---- list the disks in system
SELECT DISK n ----n is number of disk with hidden volume
DETAIL DISK ----- to make sure you got the right one
LIST VOLUME ------lists the volumes in the system
SELECT VOLUME n ----n is the number of the hidden volume
DETAIL VOLUME ---- to make sure you got the right one
ATTRIBUTES VOLUME CLEAR HIDDEN ---clear the hidden attribute
EXIT --- exit from DiskPart
EXIT --- exit from command shell

Later if you want to hide the volume again then the command is:
ATTRIBUTES VOLUME SET HIDDEN

This is another posting showing "how to do computing" for everyday computer usages... For a general public

How to format USB drive using Linux terminal ..

How to format USB with Linux terminal ..  

[ Formatting a USB in Ubuntu or linux is as easy as make filesystem (mkfs).
mkfs and tab will show you all the filesystem types you can use:

[anc@localhost~]$ mkfs
mkfs mkfs.ext3 mkfs.jfs mkfs.ntfs mkfs.vfat
mkfs.cramfs mkfs.ext4 mkfs.minix mkfs.reiserfs mkfs.xfs
mkfs.ext2 mkfs.ext4dev mkfs.msdos mkfs.udffs

To format a USB drive all you need to know is its name, this can be found by
typing df at a terminal:

[anc@localhost~]$ df -hT
Filesystem Type Size Used Avail Use% Mounted on
--snip
/dev/sdc1 ext3 3.6G 3.3G 134M 97% /media/disk


In the above example my USB is sdc1 and is a 4G USB stick. As you can see
I changed it from NTFS to ext3.

FAT32 and NTFS are weak filesystems, not only are they prone to losing data but also
require constant defragging. Most linux filesystems (except ext2) are journalled. Thye never require defragging and have better security- the disadvantage is that if you format a USB memory stick as ext3 it cant be read under windows.

To answer your earlier question,

mkfs.vfat /dev/sdc1
mkfs.ntfs /dev/sdc1

would make FAT32 and NTFS filesystems on a memory stick called sdc1

Hope that helps. ]


[ This is another posting showing "how to do computing" for everyday computer usages... For a general public ]

md5sum.exe introduction

After you download all the Shorten (.shn) files for a particular disc or show, you want to verify that the files are not corrupted or otherwise unusable before you burn them to disc or host them on your file server. We do this by checking the downloaded Shorten (.shn) files against an .md5 file. An .md5 is a simple text file that contains a "fingerprint" of each Shorten file.

When you perform an md5 check, you are comparing the fingerprint from the files you downloaded to the fingerprint of the files on the server you downloaded from. If the md5's (fingerprints) match, you have an uncorrupted Shorten file.

 md5sum.exe - 48KB         88170 Downloads since 9/29/00

Windows 95/98/Me: Download md5sum.exe to c:\windows\command

Windows NT/2000: Download md5sum.exe to your c:\winnt\system32

 

Open an MS-DOS window and go to the directory of the show you want to check. When you are in that directory, type:

md5sum -c [filename].md5
 

You must insert the name of the .md5 file [without the brackets]. Below is an example of a successful md5sum check:

   

On the other hand, if a track does not pass the md5check, you will see the following:

If any Shorten files do not pass the .md5 check, you should delete the offending file(s), and try re-downloading. Then run the .md5 check again. The file(s) should now pass the .md5 check.

If the same files fail an .md5 check more than twice, you should contact the FTP Siteop you downloaded the files from and let them know what tracks are giving you a problem. They may be hosting a corrupted track without knowing it.

Open an MS-DOS window and go to the directory of the show you want to create an .md5 file for. When you are in that directory, type:

md5sum *.shn > [filename].md5
 

NOTE: You must insert the name of the .md5 file [without the brackets]. Example:
 

md5sum *.shn > ph94-06-26d1.md5

An .md5 file will be created and placed in that directory. Please remember to adhere the etree.org naming scheme when naming .md5 files!

Please remember to always .md5 check your Shorten files before burning!

  
Special thanks to bruce@gridpoint.com and the PCP community for compiling this special version of md5sum. Documentation and graphics by Mike Wren.


 

Code - breaking ( PHP programming ) Warming up

For some time I've developing stuff in PHP .. Like experimenting stuff Its a very interesting language
to experiment with .. As it is the same with Java, Python, PHP, C++ and Ruby&Rails ....


Today, I felt like talking about php .. One, think there is one important think to say to anyone willing to learn and programm in PHP, for you to run and develop php on your computer, its  necessary to have a server running on the machine that will be used to develop and write the php code ..


It might sound quite complicated but its very simple ...To setup a server on your own computer just download Xampp for Windows, LAMP for Linux, or MAMP for Mac OS (Apple).

After your download it and install it and run properly the server you will able to see you php files via-localhost on your browser. This post isn't about how to install your server and run the localhost .. But I can explain it on another post .. For now, lets just focus on PHP coding.

 The simple and first thing on any programming language is the

 "Hello World"

 "
<html>
<head>
<title> Test PHP </title>
</head>
<body>
<?php
echo " Hello World ! ";
?>"
</body>
</html>
"
That's it simple ....

O Browser will see somethink like this;