,

Your IP Address

what is my ip address?

All in one TV sender – What is it & what does it do?

In this modern age it is very common to have more than one TV in your house. As well as the one in the living, you may have one in the kitchen, one in the second sitting room, one in the study and one in any number of bedrooms. The convenience of having multiple TVs far outweighs the extra cost of buying several televisions, but when it comes to getting the TV signal to all the TVs in your house, it can be very expensive and inconvenient. It normally involves running wires around your house, purchasing extra satellite or cable receivers, as well as additional DVD players. However, with an inexpensive All-in-one TV sender these problems will be a thing of the past.
An All-in-one TV sender transmits audio and video signals wirelessly from your main TV to a second TV located somewhere else in your house. The whole set-up is ridiculously simple in comparison to the wired and expensive alternatives. You simply plug the sender into your TV, satellite, cable, Freeview receiver or DVD player using a scart socket (something which every modern audio-visual device has) and then plug the receiver into the TV you want to watch the signal on (also using a scart connection). Both the sender and receiver units require power, but this just means plugging them into a normal wall-socket. Then you are ready to watch the video signal in the new location. As you buy the sender and receiver as an all-in-one set there`s no complicated set-up procedure because they are designed to work together with no hassle and no fuss.
In addition to sending the audio and video signals from the transmitter to the receiver, you may also want to send control commands from the receiver to the sender to tell it to change the channel, volume, or pause a DVD. For this you will require an infra-red eye to go with your receiver. An All-in-one sender comes complete with this infra-red eye, enabling you to use your original remote control to control the signal from the secondary TV as if you were in front of the primary TV. This certainly beats having to return to the primary TV every time you want to switch channel, but it does still mean you have to carry the remote back and forth between the two TVs depending on which one you want to watch. A better solution is to buy an additional remote control, so you can keep one with the wireless receiver permanently.
As the name suggests, the an All-in-one TV sender includes everything you need to send audio and video signals from one TV to another with very little hassle and for a small fraction of the cost of all other alternatives. The only problem that can occur is that of inference of the wireless signal from other wireless devices (such as a baby monitor), but there is normally an easy solution to such problems. An All-in-one sender solves all your TV needs within your house, all you really need in addition is a portable digital TVfor when you are travelling and you never have to be without a TV.
EMID – EM-CL1
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Adding Windows Components into Add/Remove Programs

Not a fan of MSN Messenger? Don't want Windows Media Player on your system?

But if you'll go to Add/Remove Programs in the Control Panel, by default none of Windows XP's built in programs are visible.


But if you want you can make them visible its just tricky but some what easy also so to make visible windows XP's built in programs follow the following some steps:

* Go to the drive where XP is installed lets say it is C:\

* open the file C:\Windows\inf\sysoc.inf in Notepad. You should see a section of the file something like this:


[Components]
NtComponents=ntoc.dll,NtOcSetupProc,,4
WBEM=ocgen.dll,OcEntry,wbemoc.inf,hide,7
Display=desk.cpl,DisplayOcSetupProc,,7
Fax=fxsocm.dll,FaxOcmSetupProc,fxsocm.inf,,7
NetOC=netoc.dll,NetOcSetupProc,netoc.inf,,7
iis=iis.dll,OcEntry,iis.inf,,7
com=comsetup.dll,OcEntry,comnt5.inf,hide,7
dtc=msdtcstp.dll,OcEntry,dtcnt5.inf,hide,7
IndexSrv_System = setupqry.dll,IndexSrv,setupqry.inf,,7
TerminalServer=TsOc.dll, HydraOc, TsOc.inf,hide,2
msmq=msmqocm.dll,MsmqOcm,msmqocm.inf,,6
ims=imsinsnt.dll,OcEntry,ims.inf,,7
fp_extensions=fp40ext.dll,FrontPage4Extensions,fp4 0ext.inf,,7
AutoUpdate=ocgen.dll,OcEntry,au.inf,hide,7
msmsgs=msgrocm.dll,OcEntry,msmsgs.inf,hide,7
RootAutoUpdate=ocgen.dll,OcEntry,rootau.inf,,7
IEAccess=ocgen.dll,OcEntry,ieaccess.inf,,7


* This is a list of all components installed at the moment. I've taken the example of MSN Messenger - the program entry called 'msmsgs', third-last line. You can see the word 'hide' highlighted (hide is the string which tells Windows not to display the component in the Add/Remove Programs list).

* Fix this up by simply deleting the word 'hide' like so:

msmsgs=msgrocm.dll,OcEntry,msmsgs.inf,hide,7

* To this:

msmsgs=msgrocm.dll,OcEntry,msmsgs.inf,,7

* Now, after restarting, you should be able to see MSN Messenger in the Add/Remove Programs list.



Imp: If you want to be able to quickly view and remove all components, simply open the sysoc.inf file and do a global find and replace for the word ",hide" and replace it with a single comma ",".
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Create Nameless Folder in Windows XP

This trick works only in Windows 2000 and Windows XP.Following are the steps required to pull off this nice piece of trick.
step 1. Select any file you wish.
step 2. Right-click the file and click Rename or just press the F2 key to rename it.
step 3. Press and hold the ALT key. While still holding the Alt key, type the numbers 0160 from the keyboard.(Note: The numbers must be typed from the numpad of your keyboard. i.e the number keys present on the right side of the keyboard and NOT from the number keys present above the top of character keys.)
step 4. The file will be without a nameWhat happens here is, the file is named with a single space.

If you want to create a second file without a name in the same directory as the first one, the above steps will not help you.So how do you create a second "nameless" file?
1. Follow the first 3 steps mentioned above.
2. Release the ALT key. Again repeat the first 3 steps.
3. Now the second file will be created with two spaces.
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Power On Self Test Beep Codes for AMI and Phoenix BIOS

When an IBM compatible computer is first turned on, the hardware runs a Power-On Self Test (POST). If errors are encountered during this POST test, they are usually displayed via an audio beep or in the form of a code number flashed across the screen. With this audio code in hand, you can determine what part of the system is having problems and find a solution.

The pattern of beeps whether its the number of beeps or the length of those beeps will give you an indication of the actual problem. Its a distress signal from the computer in a morse code like pattern. Unless you have a diagnostic card to tell you more about the particular problem, you will have to use the charts below to decipher the computer error and get your machine back up and running.


Standard Original IBM POST Error Codes

1 short beep --------------- Normal POST - system is ok
2 short beeps--------------- POST Error - error code shown on screen
No beep ----------------------Power supply or system board problem
Continuous beep------------Power supply, system board, or keyboard problem
Repeating short beeps-----Power supply or system board problem
1 long, 1 short beep---------System board problem
1 long, 2 short beeps--------Display adapter problem (MDA, CGA)
1 long, 3 short beeps--------Enhanced Graphics Adapter (EGA)
3 long beeps ------------------3270 keyboard card


AMI BIOS Beep Codes

1 Short Beep -------One beep is good! Everything is ok, that is if you see things on the screen. If you don't see anything, check your monitor and video card first. Is everything connected? If they seem fine, your motherboard has some bad chips on it. First reset the SIMM's and reboot. If it does the same thing, one of the memory chips on the motherboard are bad, and you most likely need to get another motherboard since these chips are soldered on. 

2 Short Beeps---------Your computer has memory problems. First check video. If video is working, you'll see an error message. If not, you have a parity error in your first 64K of memory. First check your SIMM's. Reseat them and reboot. If this doesn't do it, the memory chips may be bad. You can try switching the first and second banks memory chips. First banks are the memory banks that your CPU finds its first 64K of base memory in. You'll need to consult your manual to see which bank is first. If all your memory tests good, you probably need to buy another motherboard. 

3 Short Beeps -------Basically the same thing as 2 beeps. Follow that diagnosis above. 
4 Short Beeps --------Basically the same thing as 2 beeps. Follow that diagnosis above. It could also be a bad timer 
5 Short Beeps --------Your motherboard is complaining. Try reseating the memory and rebooting. If that doesn't help, you should consider another motherboard. You could probably get away with just replacing the CPU, but that's not too cost-effective. Its just time to upgrade! 
6 Short Beeps --------The chip on your motherboard that controls your keyboard (A20 gate) isn't working. First try another keyboard. If it doesn't help, reseat the chip that controls the keyboard, if it isn't soldered in. If it still beeps, replace the chip if possible. Replace the motherboard if it is soldered in. 
7 Short Beeps --------Your CPU broke overnight. Its no good. Either replace the CPU, or buy another motherboard. 
8 Short Beeps --------Your video card isn't working. Make sure it is seated well in the bus. If it still beeps, either the whole card is bad or the memory on it is. Best bet is to install another video card. 
9 Short Beeps --------Your BIOS is bad. Reseat or Replace the BIOS. 
10 Short Beeps -------Your problem lies deep inside the CMOS. All chips associated with the CMOS will likely have to be replaced. Your best bet is to get a new motherboard.
11 Short Beeps -------Your problem is in the Cache Memory chips on the motherboard. Reseat or Replace these chips.
1 Long, 3 Short Beeps --- You've probably just added memory to the motherboard since this is a conventional or extended memory failure. Generally this is caused by a memory chip that is not seated properly. Reseat the memory chips.
1 Long, 8 Short Beeps ----- Display / retrace test failed. Reseat the video card.



Phoenix BIOS Beep Codes

These audio codes are a little more detailed then the AMI codes. This BIOS emits three sets of beeps. For example, 1 -pause- 3 -pause 3 -pause. This is a 1-3-3 combo and each set of beeps is separated by a brief pause. Listen to this sequence of sounds, count them, and reboot and count again if you have to.

1-1-3 Your computer can't read the configuration info stored in the CMOS. Replace the motherboard. 
1-1-4 
Your BIOS needs to be replaced. 
1-2-1 You have a bad timer chip on the motherboard. You need a new motherboard. 
1-2-2 The motherboard is bad. 
1-2-3 The motherboard is bad. 
1-3-1 You'll need to replace the motherboard. 
1-3-3 You'll need to replace the motherboard. 
1-3-4 The motherboard is bad. 
1-4-1 The motherboard is bad. 
1-4-2 Some of your memory is bad. 
2-_-_ Any combo of beeps after two means that some of your memory is bad, and unless you want to get real technical, you should probably have the guys in the lab coats test the memory for you. Take it to the shop. 
3-1-_ One of the chips on your motherboard is broken. You'll likely need to get another board. 
3-2-4 One of the chips on your motherboard that checks the keyboard is broken. You'll likely need to get another board. 
3-3-4 Your computer can't find the video card. Is it there? If so, try swapping it with another one and see if it works. 
3-4-_ 
Your video card isn't working. You'll need to replace it. 
4-2-1 There's a bad chip on the motherboard. You need to buy another board. 
4-2-2 First check the keyboard for problems. If nothing, you have a bad motherboard. 
4-2-3 Same as 4-2-2. 
4-2-4 One of the cards is bad. Try yanking out the cards one by one to isolate the culprit. Replace the bad one. The last possibility is to buy another motherboard. 
4-3-1 Replace the motherboard. 
4-3-2 See 4-3-1
4-3-3 See 4-3-1
4-3-4 Time of day clock failure. Try running the setup program that comes with the computer. Check the date and time. If that doesn't work, replace the battery. If that doesn't work, replace the power supply. You may have to replace the motherboard, but that is rare. 
4-4-1 Your serial ports are acting up. Reseat, or replace, the I/O card. If the I/O is on the motherboard itself, disable them with a jumper (consult your manual to know which one) and then add an I/O card. 
4-4-2 See 4-4-1, but this time is your Parallel port that's acting up.
4-4-3 You math coprocessor is having problems. Run a test program to double-check it. If it is indeed bad, disable it, or replace it.
Low 1-1-2 Your motherboard is having problems
Low 1-1-3 This is an Extended CMOS RAM problem, check your motherboard battery, and motherboard.




IBM POST(Power On Self Test ) Diagnostic Code Descriptions

100 - 199 System Board
200 - 299 Memory
300 - 399 Keyboard
400 - 499 Monochrome Display
500 - 599 Color/Graphics Display
600 - 699 Floppy-disk drive and/or Adapter
700 - 799 Math Coprocessor
900 - 999 Parallel Printer Port
1000 - 1099 Alternate Printer Adapter
1100 - 1299 Asynchronous Communication Device, Adapter, or Port
1300 - 1399 Game Port
1400 - 1499 Color/Graphics Printer
1500 - 1599 Synchronous Communication Device, Adapter, or Port
1700 - 1799 Hard Drive and/or Adapter
1800 - 1899 Expansion Unit (XT)
2000 - 2199 Bisynchronous Communication Adapter
2400 - 2599 EGA system-board Video (MCA)
3000 - 3199 LAN Adapter
4800 - 4999 Internal Modem
7000 - 7099 Phoenix BIOS Chips
7300 - 7399 3.5" Disk Drive
8900 - 8999 MIDI Adapter
11200 - 11299 SCSI Adapter
21000 - 21099 SCSI Fixed Disk and Controller
21500 - 21599 SCSI CD-ROM System
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10 reasons why PCs crash U 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 a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall 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. 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.

A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.

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.
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Computer Virus and its types

A computer virus is a computer program that can copy itself and infect a computer without permission or knowledge of the user. The term "virus" is also commonly used, albeit erroneously, to refer to many different types of malware and adware programs. The original virus may modify the copies, or the copies may modify themselves, as occurs in a metamorphic virus.

A virus can only spread from one computer to another when its host is taken to the uninfected computer, for instance by a user sending it over a network or the Internet, or by carrying it on a removable medium such as a floppy disk, CD, or USB drive.

Meanwhile viruses can spread to other computers by infecting files on a network file system or a file system that is accessed by another computer.

Viruses
A virus is a small piece of software that piggybacks on real programs. For example, a virus might attach itself to a program such as a spreadsheet program. Each time the spreadsheet program runs, the virus runs, too, and it has the chance to reproduce (by attaching to other programs) or wreak havoc.

E-mail viruses 
An e-mail virus travels as an attachment to e-mail messages, and usually replicates itself by automatically mailing itself to dozens of people in the victim's e-mail address book. Some e-mail viruses don't even require a double-click -- they launch when you view the infected message in the preview pane of your e-mail software

Trojan horses 
A Trojan horse is simply a computer program. The program claims to do one thing (it may claim to be a game) but instead does damage when you run it (it may erase your hard disk). Trojan horses have no way to replicate automatically.

Worms
A worm is a small piece of software that uses computer networks and security holes to replicate itself. A copy of the worm scans the network for another machine that has a specific security hole. It copies itself to the new machine using the security hole, and then starts replicating from there, as well.

What They Infect

Viruses can infect several files of the computer's operating and file system. These include:

* System Sectors
* Files
* Macros
* Companion Files
* Disk Clusters
* Batch Files
* Source Code


How They Infect :
Viruses are sometimes also categorized by how they infect.

* Polymorphic Viruses
* Stealth Viruses
* Armored Viruses
* Multipartite Viruses
* NTFS ADS Viruses
* Mutated viruses
* Macro viruses

How They Infect 

Viruses are sometimes also categorized by how they infect.

* Polymorphic Viruses
* Stealth Viruses
* Armored Viruses
* Multipartite Viruses
* NTFS ADS Viruses
* Mutated viruses
* Macro viruses


Polymorphic Viruses
To confound virus scanning programs, virus writers created polymorphic viruses. These viruses are more difficult to detect by scanning because each copy of the virus looks different than the other copies.

Stealth Viruses

A stealth virus hides the modifications it makes. It does this by taking over the system functions which read files or system sectors and, when some other program requests information from portions of the disk the virus has changed, the virus reports back the correct (unchanged) information instead of what's really there (the virus). Of course, the virus must be resident in memory and active to do this.

Armored Viruses

Armored is a class that overlaps other classes of viruses; maybe multiple times.Basically, an armored virus uses special "tricks" designed to foil anti-virus researchers.

Multipartite Virus

Some viruses can be all things to all machines. Depending on what needs to be infected, they can infect system sectors or they can infect files. These rather universal viruses are termed multipartite (multi-part).Sometimes the multipartite virus drops a system sector infector; other times a system sector infector might also infect files.

NTFS ADS Viruses

The NT File System (NTFS) contains within it a system called Alternate Data Streams (ADS). This subsystem allows additional data to be linked to a file. The additional data, however, is not always apparent to the user. Windows Explorer and the DIRectory command do not show you the ADS; other file tools (e.g., COPY and MOVE) will recognize and process the attached ADS file
The ADS file is effectively hidden from view.

Mutated viruses

In reality, most viruses are clones, or more precisely "mutated viruses" — viruses which have been rewritten by other users in order to change their behavior or signature.

The fact that multiple versions of the same virus (called variants) exist makes dection all the more difficult, as antivirus software publishers then have to add these new signatures to their databases.

Macro viruses

With the increase in programs which use macros, Microsoft has developed a shared script language which can be inserted into most types of documents which can contain macros. It's called VBScript, a subset of Visual Basic. These viruses are currently able to infect macros in Microsoft Office documents, meaning that such a virus can be placed within an ordinary Word or Excel document and run a portion of code when the file is opened, so that the virus can both spread into files and access the operating system (generally Windows).

Other Threats

Viruses and worms get a lot of publicity, but they aren't the only threats to your computer's health. Malware is just another name for software that has an evil intent. Here are some common types of malware and what they might do to your infected computer:


malware

Most personal computers are now connected to the Internet and to local area networks, facilitating the spread of malicious code. Today's viruses may also take advantage of network services such as the World Wide Web, e-mail, Instant Messaging and file sharing systems to spread, blurring the line between viruses and worms. Furthermore, some sources use an alternative terminology in which a virus is any form of self-replicating malware.
Malicious programs can be divided into the following groups: worms, viruses, Trojans, hacker utilities and other malware. All of these are designed to damage the infected machine or other networked machines.

Adware : They puts ads up on your screen.

Spyware :They collects personal information about you, like your passwords or other information you type into your computer.

Hijackers : They turn your machine into a zombie computer.

Dialers : They force your computer to make phone calls. For example, one might call toll 900-numbers and run up your phone bill.
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