Trojan Horse Virus. Review on Improving Your Computer's Performance

A Trojan Horse is an email virus usually released by an email attachment, It is a program that appears to be legitimate, but in fact does something malicious. Quite often, that something malicious involves gaining remote, surreptitious access to a user's system. Unlike viruses, a Trojan does not replicate(i.e. infect other

files), nor does it make copies of itself as worms do. There are different types of Trojans. Some of these include: remote access Trojans(RATs), backdoor

Trojans(backdoors), IRC Trojans(IRCbots), and keylogging Trojans. Many Trojan

encompass multiple types. For example, a Trojan may install both a keylogger

and a backdoor. IRC Trojans are often combined with backdoors and RATs to

create collections of infected computers known as botnets.

But one thing you probably

won't find a Trojan doing is scouring your hard drive for personal details, as

the Visa description alleges. Contextually, that would be a bit of a trick for

a Trojan. Instead, this is where the keylogging functionality most often comes

into play - capturing the user's keystrokes as they type and sending the logs

to the attackers. Some of these keyloggers can be pretty sophisticated,

targeting only certain websites(for example) and capturing any keystrokes

involved with that particular session.

But why is it important to

know the difference between a virus, a worm, and a Trojan? Because a virus

infects legitimate files, thus if antivirus software detects a virus,

that file should be cleaned. Conversely, if antivirus software detects a

worm or a Trojan, there is no legitimate file involved and action should be to delete

the file.

This virus is a common yet difficult to remove computer threat and works

by hiding within a set of seemingly useful software programs. Once executed or

installed in the system, this type of virus will start infecting other files in

the computer.

Another method used by

malware developers to spread their Trojan Horse viruses is via chat software

such as Yahoo Messenger and Skype. Another method used by this virus in order

to infect other machines is through sending copies of itself to the people in

the address book of a user whose computer has already been infected by the

virus.

The best way to prevent a

Trojan Horse Virus from entering and infecting your computer is to never open

email attachments or files that have been sent by unknown senders. However, not

all files we can receive are guaranteed to be virus-free. With this, a good way

of protecting your PC against malicious programs such as this harmful

application is to install and update an antivirus program.

Recovering from a Trojan

Horse or Virus *

If you know what specific malicious program has infected your

computer, you can visit one of several antivirus web sites and download a

removal tool. Chances are, however, that you will not be able to identify the

specific program. Unfortunately your other choices are limited, but the

following steps may help save your computer and your files.

      1.     *Disconnect

your computer from the Internet *

Depending on what type of virus you have, intruders may have access to your personal information and may

even be using your computer to attack other computers. You can stop this

activity by turning off your Internet connection. The best way to accomplish

this is to physically disconnect your cable or phone line, but you can also

simply “disable” your network connection.

      2.     *Back

up your important files *

At this point it's a good idea to take back up of ur files. If possible, compile all of ur photos, documents,

Internet favorites, etc., and burn them onto a CD or DVD or save them to some

other external storage device. It is vital to note that these files cannot be

trusted, since they are still potentially infected.

      3. Scan your machine

Since your computer may be infected with a malicious program, it is safest to

scan the machine from a live CD(or “rescue” CD) rather than a previously

installed antivirus program. Many antivirus products provide this

functionality. Another alternative is to use a web-based virus removal service,

which some antivirus software vendors offer(try searching on “online virus

scan”). Or you could just try Microsoft’s web-based PC Protection Scan. The

next best action is to install an antivirus program from an uncontaminated

source such as a CD-ROM. If you don’t have one, there are many to choose from,

but all of them should provide the tools you need. After you install the

software, complete a scan of your machine. The initial scan will hopefully

identify the malicious program(s). Ideally, the antivirus program will even

offer to remove the malicious files from your computer; follow the advice or

instructions you are given. If the antivirus software successfully locates and

removes the malicious files, be sure to follow the precautionary steps in Step

7 to prevent another infection. In the unfortunate event that the antivirus

software cannot locate or remove the malicious program, you will have to follow

Steps 5 and 6.

*      4. Reinstall your operating

system *

If the previous step failed to clean

your computer, the most effective option is to wipe or format the hard drive

and reinstall the operating system. Although this corrective action will also

result in the loss of all your programs and files, it is the only way to ensure

your computer is free from backdoors and intruder modifications.

Many computer vendors also offer a

rescue partition or disc(s) that will do a factory restore of the system. Check

your computer’s user manual to find out whether one of these is provided and

how to run it.

Before conducting the reinstall, make

a note of all your programs and settings so that you can return your computer

to its original condition.

It is vital that you also reinstall

your antivirus software and apply any patches that may be available. Consult

“Before You Connect a New Computer to the Internet” for further assistance.

      5. Restore your files

If you

made a backup in Step 3, you can now restore your files. Before placing the

files back in directories on your computer, you should scan them with your

antivirus software to check them for known viruses.

      6. Protect your computer

To prevent future infections, you

should take the following precautions:

• Do not open unsolicited attachments

in email messages. • Do not follow unsolicited links. • Maintain updated

antivirus software. • Use an Internet firewall.

• Secure your web browser.

• Keep your system patched.