Before attempting to remove a Trojan, first you should understand how a Trojan is able to infiltrate your computer and what damage it can do. Trojan’s aren’t true viruses, as they don’t replicate themselves.

A Trojan is malware. Malware is software that is designed to infiltrate or damage your computer without your knowledge, which is similar to spyware, adware, and viruses also. A Trojan is a stealthy and sneaky program that exists to cause damage to you and your computer.

Some examples of what Trojan’s are programmed to do are:

Spreading other malware, such as viruses.

Erasing or overwriting data on your computer.

Allowing remote access to your computer.

Setting up networks of other computers in order to launch DDoS [Distributed Denial of Service Attack] or send spam.

Spying on your computer and silently reporting data such as browsing habits to sender of the Trojan.

Logging keystrokes to steal information such as passwords, credit card and bank account details.

Phishing for bank or other account details, which can be used for criminal activities.

Installing a backdoor on a computer system, so your computer can be used without your knowledge or permission.

Collecting e-mail addresses and using them for spam.

Deactivating or interfering with anti-virus and firewall programs.

Randomly shutting off your computer.

How Did A Trojan Infect Your Computer?

A Trojan is able to gain access to your computer because it pretended to be an innocent or helpful program, or because you download movies, music or software illegally. Once the Trojan is activated, normally by you clicking on it thinking it’s a useful program, it will start the job it was programmed for.

It will do this silently in the background without your knowledge and so will often only interfere a little with your computer, choosing to do their dirty work while your machine is idle. Computers left on and connected to the internet while you are asleep, at work or school are favourite targets.

Removing a Trojan can be tricky as they hide themselves in the computers registry files and manual deletion is not recommended. Trojans can also disguise themselves as software your computer in reality needs, you could accidentally delete an essential program or system registry entry. This could result in your computer not being able to boot up.

Signs You May Have a Trojan

If you notice any of the following then you could potentially have a Trojan:

When you’re not using the computer for Internet access your computer modem or router is whirring away, or the lights are blinking wildly.

Your Internet connection speed has constantly slowed to a crawl.

Your anti-virus and/or anti-spyware have been deactivated.

Strange icons appearing on your desktop.

Your computer start up speed has reduced alarmingly.

You could have a shower in the time it takes to open up a file.

Prevention

Be careful when opening files and especially email attachments from people you do and do not know. If in doubt, do not open the file. Using CD’s, USB drives and more likely downloading the Trojan are the most common ways of your computer becoming infected.

Try not to download movie, music or software files that you know are meant to be paid for. Most of all files that are downloaded this way contain Trojans. If other people use your computer educate them too. Ensure they have user profiles, and that they have restricted profiles if necessary.

Cure

If you find that you have a Trojan, then ensure you run your anti-virus and anti-spyware programs. They should be able to remove them. If the Trojan is stubborn, then boot your computer into safe-mode and run the anti-virus and anti-spyware, this should remove the culprit.

If this doesn’t remove the offending Trojan, then maybe invest in a stronger anti-virus and or anti-spyware program. A good anti-virus/spyware program should be able to remove a Trojan program from your computer.

By following the above suggestions you will stand a much better chance of preventing your computer from being infected by a Trojan, and removing one should you need to.