Of course it's vital to have Trojan horse detection software installed on all of your business computers. As a savvy business owner, however, you also know that it's just as important to prevent fires as to fight them. As the saying goes, an ounce of prevention is worth a pound of cure!

When you're aware of what's going on in the world of Trojan horses, you're much less likely to suffer their attacks. To arm yourself with the knowledge you need to prevent unnecessary downtime in your office, you can:

1. Prevent Trojan horse infection by surfing the web from the safety of an Internet sandbox.
2. Protect yourself by becoming aware of latest Trojan horse alerts.
3. Read the latest anti-Trojan guides and white papers.
   

Action Steps
The best contacts and resources to help you get it done

Eliminate the need for a post-infection Trojan horse remover by surfing in a virtual sandbox

Installing a virtual sandbox allows you to run unknown programs in a completely isolated environment. It will block viruses--such as a Trojan horse virus--from actually infecting your computer by only allowing it to run inside a synthetic location called a 'sandbox.' This is one of the more creative trends of ways to avoid infection, which negates the need for costly after-the-fact trojan horse removal software.

I recommend: You can download the latest version of Virtual Sandbox from the Fortres Grand Corporation website. At Gizmo's Tech Support Alert, you can keep up with browser protection sandbox utilities with informative reviews. Here, you can also find download links for three of the best sandbox utilities.

Keep up-to-date with the latest Trojan horse news and alerts

New Trojan horses and virus are constantly emerging on the scene. There are a variety of methods available to you to keep yourself aware of the latest threats.

I recommend: Sign up for the McAfee Avert® Labs Threat News alert to get the latest threats sent directly to your inbox. The Kaspersky Lab has an excellent website dedicated to posting all the latest virus and Trojan alerts. Get the most current Trojan horse news and trends at the Panda Security website. You can even subscribe to RSS virus alerts directly on the site.

Read the latest literature on how to best combat Trojan horse viruses

In conjunction with keeping up with the latest virus alerts, you should also be aware of latest information in the fight against Trojan horses. Learn how best to protect yourself with anti-Trojan guides and white papers.

I recommend: Read the excellent, up-to-date Anti-Trojan Guide at the website of Henry Stephen Markus. Freebyte.com links to an excellent white paper on how to prevent Trojan horse infections.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  One of the best preventative measures at your disposal is your current Trojan virus remover. Make sure that your Trojan remover software is set to download daily definition updates. This will offer you the best level of protection against an ever-changing and threatening Internet landscape.

A Trojan horse is a computer program that performs one function while appearing to perform another. Trojan horses are notorious for their use in installing backdoor programs to allow unauthorized access of a computer system by another program or hacker.

A Trojan horse program may infect a computer by posing as a screensaver because the application runs constantly in the background. Once installed, it can place all sorts of commands, programs and scripts on a computer without the user's knowledge. The most common purposes of malicious Trojan horses are to run downloaders and servers on the end-user's system. They are also used to launch remote denial-of-service attacks.

Trojan horses do not have to be malicious and may be used to install legitimate software and manage computer systems. They are also used in law enforcement for surveillance and computer forensics.

Safeguard a computer network against Trojan horses by:

1. Setting up a routine for employees to follow;
2. Installing software to seek and destroy Trojans;
3. Searching manually for Trojan horses.
   

Action Steps
The best contacts and resources to help you get it done

Perform general Trojan horse removal by following some basic procedures

Trojan horses must modify many of the same system files to be successful. You can control many Trojan horses on a network by requiring users to follow certain steps on a regular basis.

I recommend: Follow the instructions at Symantec for a good general purpose attack on Trojan horses. Macworld offers a general primer on detecting Trojan horses for the Mac OS X.

Buy Trojan horse detection software

Trojan horse detection software uses two basic methods to detect Trojan horses. The software may compare suspect code to a signature list that contains the identifying characteristics of known Trojan horses. Trojan remover software also may look for the type of behavior that a Trojan horse frequently exhibits.

I recommend: Look for small business and enterprise solutions to Trojan horse removal at Symantec. It is one of the most experienced companies for Trojan horse removal software. Spybot is a free Trojan removal tool that specializes in removing spyware, a type of Trojan horse virus that monitors user activity.

Remove specific Trojan horses

A Trojan horse may have to be removed manually if your Trojan horse removal software does not have it in its signature list. While a Trojan horse remover generally has its signature list updated each month, you may need to visit a forum to find a solution to your Trojan horse infection.

I recommend: Find extensive discussions on removing specific Trojan horses at the Bleeping Computer forums. These forums are heavily trafficked and receive hundreds of posts on Trojan horses each day. Techspot.com also provides current information on the latest Trojan horses.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Take some steps that your Trojan horse remover will not be able to perform well. Check the running processes on your computer frequently. Look for processes with unfamiliar names, especially those that seem to be composed of random letters.
• •  Be alert for prolonged and continuous disk activity when your computer should be idle. While this frequently indicates that you are simply low on disk space, it can also mean that your computer is being used as a server.

As a small business owner infected with a Trojan horse, you want the quickest and cheapest route back to functionality. You probably have McAfee or Norton, and have had some scary pop-up that keeps coming up over and over. Your antivirus hasn't been able to get rid of it, so what next?

You can easily spend between $200 and $500 hiring a computer repair service to remove a Trojan horse from your computer. That's a big financial hit for a small company, especially in tight economic times. The path to making the most of Trojan horse removal lies in finding the quickest and most cost effective methods of getting back on your feet, and finally getting your files backed up in the process:

1. Don't even mess with it—back up your data and do a fresh install of Windows.
2. Download and run the ComboFix Trojan horse removal software.
3. Install, update and run a SuperAntiSpyware complete system scan.
   

Action Steps
The best contacts and resources to help you get it done

Get rid of your Trojan horse by backing up your files and reinstalling Windows from scratch

If you don't have the slightest idea of how to remove a Trojan, and want the simplest if slightly more time-consuming solution, a fresh reinstall if Windows will usually do the trick. The up-side is this is the easiest way to be sure that the Trojan is completely gone from your system. You can backup your data to an external hard drive, burn it to CD or DVD, or even put it on a USB key. Once your files are backed up, use the Windows Disk or Recovery Disks that came with your computer to do a fresh install of Windows--ensuring that your entire hard drive is formatted.

I recommend: The Argentum Corporation backup guide does a great job pointing you to the location on your hard drive where you can find your Outlook data files, important document files and even messenger data. You can backup yourself on any media, but if you feel more comfortable letting something else do it, they have pretty cheap backup software for sale on their site. WindowsReinstall has excellent guides on how to do a reinstall of Windows 2000, XP Home or Pro and even Windows Vista.

Run a scan with the best Trojan remover software: ComboFix

If backing up your data and starting from scratch isn't an option, your best chance for getting rid of a Trojan horse virus is to use some first-class trojan horse detection software. Most computer technicians use ComboFix as their first step in Trojan and virus removal. Make sure your data has been backed up and that you thoroughly read the instructions before running ComboFix.

I recommend: Download the latest version of Combofix to your desktop from the Icrontic forum. There is a guide to using Combofix at Bleeping Computer.

Download and run SuperAntiSpyware as your secondary Trojan horse remover

ComboFix does an excellent job of getting rid of an active infection, but it won't get rid certain inactive infected files or clean out any infected system restore points. For that reason, it's always good to run a SuperAntiSpyware scan after ComboFix runs.

I recommend: Download the free version of SUPERAntiSpyware from their website. Always update the program with the latest definitions before running a complete system scan. Read a tutorial on using the program at Help2Go.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  It's easy to lose faith in your antivirus software when it detects Trojan horses but then fails to remove them. Just remember that for every virus it can't remove, you're being protected from thousands of others. No matter what, you'll never be irreparably harmed if you regularly back up your data.

Although the terms worm, trojan horse and virus are often used interchangeably, they are not exactly the same thing. All three are malicious programs that can be damaging to your computer, data or personal identity. Blended threats combine aspects of all three in more sophisticated attacks that range from simply annoying to utterly damaging. Knowing the difference will make you more aware of existing threats and protect you from infection in the future.

Action Steps
The best contacts and resources to help you get it done

Virus

A computer virus works by attaching itself to an executable file. If the file is not physically opened or run, your computer doesn't become infected. Viruses, therefore, can't spread without human interaction. Most viruses are spread by the forwarding of infected email attachments.

I recommend: Learn about the inner workings of computer viruses at HowStuffWorks.

Worm

A worm is actually a sub-class of virus. Worms are unique in that they are capable of spreading without human interaction. Some worms replicate by sending themselves out to everyone in your address book. Because of their copying nature and ability to spread across networks and the Internet, worms are much more widespread and damaging than typical viruses.

I recommend: Learn about the among between viruses, worms and trojans at WebMediaBrands.

Trojan horse, or backdoor virus

The term 'trojan horse' is derived from the method the Greeks used to enter the city of Troy. It has come to mean any trick that causes a target to invite an enemy into a secure location. A trojan horse-or backdoor virus-is technically not a virus at all. It is a malicious program that masquerades as a desirable or legitimate program to gain entry to your system. Often the trojan horse is the means by which a virus can enter your system. The trojan horse is the system of delivery and the virus is the payload.

I recommend: Learn about the different types of trojan horse infections at Blue Whale Web.

Payload

The payload of a trojan horse is the code it carries within it. For the most part, the cargo it carries is malicious. The payload can be anything from keyloggers to virus downloaders, and even viruses meant to destroy data.

I recommend: Learn about the different types of trojan horse payloads at AnVir Software.

Blended threat

A blended threat is a bundle of malicious programs that combines the functionality of viruses, worms and trojan horses. As security programs have become more advanced, so have virus writers. Malicious programs have become exponentially more complex.

I recommend: Find out more about blended threats at TechTarget or the Kaspersky Lab.

Trojan removal

Anti-virus programs and anti-spyware, or anti-malware programs, now perform overlapping functions. All three can usually detect and remove trojans. Because individual programs have varying degrees of success against different trojans, it is important to run more than one scan to ensure thorough trojan removal.

I recommend: Bleeping Computer has an excellent guide to trojan removal.