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PC Security

PC Security

The uses of the Internet are limitless. We use computers and the Internet for everything from banking and investing, to shopping and communicating with others via email or chat programs. The Internet has become an important part of our lives. Even as you casually surf, shop and play, you may not consider your communications as "top secret". However, you probably do not want strangers reading your email, using your computer to attack other systems, sending forged email from your computer, or examining personal information stored on your computer (such as financial statements). Without using a firewall and antivirus software, connecting to the Internet is like leaving your door unlocked when you go out -- if you're lucky you'll come home to find that all is well, but it's still risky

The following information is intended to help you understand a little bit more about how to protect your computer.

Virus and Antivirus Software

What is Virus?

A computer virus is a program designed to spread itself by first infecting executable files or the system areas of hard and floppy disks and then making copies of itself. Viruses usually operate without the knowledge or desire of the computer user.

There are two kinds of well known viruses - Worms and Trojans
Worms are self-replicating files that don't need a host program as traditional viruses do. They exploit some network security flaw to travel from computer to computer, or sometimes replicate themselves throughout a single computer. Once the program is copied to a new site, it seeks out a security hole leading to yet another site and copies itself there.

Trojan horses, a background program, do not necessarily self-replicate, although many of them do. These pests pretend to be something beneficial when they are really a means of attacking your computer. A Trojan horse may be disguised as a game or utility software, for example. It may actually contain what it says it does, but when you go to play the game or use the utility, another part of the program will be doing its dirty work.

There are several ways in which your computer can become infected and they are: through removal media such as a floppy disk, zip disk, or CD, downloading and installing a program from the Internet, opening an email attachment, and lastly, visiting a malicious website. It is good to be aware of these methods because preventing these viruses from getting in to your computer in the first place is the best line of defense.

Antivirus software

If you're not using antivirus software right now, stop what you're doing, go get one, and then continue reading after you've installed it. If you use Windows, not using antivirus software is simply irresponsible because of the high volume of viruses that target any version of this OS. Even if you think you know how to avoid viruses, you may eventually get nailed by one that employs a new and unexpected technique. If you get infected, chances are you'll infect your family members, friends, colleagues, and others who are in your address book.

There are many antivirus software products. For home office use, Symantec's Norton Antivirus and McAfee's VirusScan are two leaders in the area, but the brand name does not matter as much as the frequency of the virus updates which the company offers. There are several other reputable packages available besides these, such as Sophos AntiVirus (a well-designed and worth-the-price antivirus program best suited for networked PCs), especially for the business world.


  • Update your Windows operating system
  • Update your Antivirus software regularly
  • Scan your system regularly
  • Don't run programs of unknown origin

Spyware and SpyBot Search & Destroy

Spyware, also known as Adware, is software that sneaks onto your computer and watches what you do without the user's knowledge. It gathers information about you for later retrieval by whoever controls the spyware.

The problem with spyware is not only the loss of privacy - that's bad enough, but it also can spawn pop up and pop under ads, interfere with the compatibility of your system's components, reset your browser to use another company's sites as defaults, and slow your browser.

SpyBot Search & Destroy

When it comes to keeping spyware off of your system, Spybot Search & Destroy is the most popular free software available now. Like all antispyware applications, Spybot scans your computer's active memory and hard drive for pesky programs that add unwanted advertising or track your online moves. Its default mode is easy to use and perfect for home users; its advanced mode offers features that will please most high-end users. Spybot has wide international appeal, with its support of more than 30 different languages, and it remains available as a free download.

Microsoft Windows AntiSpyware

Windows AntiSpyware (Beta) is a security technology that helps protect Windows users from spyware and other potentially unwanted software. Known spyware on your PC can be detected and removed. This helps reduce negative effects caused by spyware including slow PC performance, annoying pop-up ads, unwanted changes to Internet settings, and unauthorized use of your private information. Continuous protection improves Internet browsing safety by guarding over fifty (50) ways spyware can enter your PC. A feature like this is a paid feature in other programs.

Microsoft put a lot of effort in their design and effectiveness of their AntiSpyware software. They have a simple to use graphical user interface that is very intuitive. Even though the interface is easy to use, the software is very effective at easily detecting spyware and offering you several options on what to do once spyware has been detected.

Also participants in the worldwide SpyNetTM(SpyNet is a community which is designed to help discover new spyware threats that exist on a PC.) play a key role in determining which suspicious programs are classified as spyware. Microsoft researchers quickly develop methods to counteract these threats, and updates are automatically downloaded to your PC so you stay up to date.
Click on the link Frequently asked questions about Microsoft Windows AntiSpyware (Beta) to get more information.


  • Use one or more antispyware programs
  • Use Firewall, such as the built-in firewall in Windows XP


Firewall is a system or group of systems that enforces an access control policy between two networks. In the context of home networks, a firewall typically takes one of two forms:
Software firewall - specialized software running on an individual computer, or
Network firewall - a dedicated device designed to protect one or more computers.

A firewall is the security guard on the front door that controls access to your computer. A good firewall will make your machine invisible to the rest of the Internet (stealth mode) while continuing to let you work as normal. Since the trend now is more and more home users are moving away from dial up Internet access, a firewall is becoming ever more important for the average user.

The trend is towards high-speed Internet access (also called broadband Internet connection). The difference between a broadband connection and a dial up connection is that the broadband connection is always on and has a static IP address. Typically with dial up connection, you are automatically signed off the Internet (after inactivity) and when you reconnect you are given a new IP. This very nature of dial up provides some protection against intruders. With broadband, because you are always on the Internet, a firewall is very necessary. Your IP address is static and a determined intruder who knows your IP can attempt to break into your computer at their leisure. Not having a firewall for your broadband connection is equivalent to leaving all of your windows and doors open when you are not home.

Firewall is a good way to prevent hackers from intruding in to your computer.


ZoneAlarm is an award winning software-based firewall. Besides its firewall feature, it includes other great features such as application control, Internet lock, and Zones. With its build in wizard, initial setup is a snap. Best of All, ZoneAlarm is free for the average home user.

A router with NAT (Network Address Translation) is your best bet for an inexpensive, but effective Network firewall. It is a good choice for setting up a network of two or more computers.

Microsoft Windows Firewall

Windows XP comes included with firewall protection software. If you have the first edition of Windows XP to Service Pack 1 your firewall software is known as Internet Connection Firewall, however, if you have Service Pack 2, it is known as Windows Firewall.

Internet Connection Firewall and Windows Firewall do what you would expect a firewall to do by controlling access to your computer, but they do differ in some aspects. Internet Connection Firewall is not enabled by default on the version of Windows XP that has it. It also may require some configuring on your part, which can be difficult if you don't know the necessary information to configure the software. Windows Firewall, on the other hand, comes turned on by default and is pre-configured for you so that you are already offered immediate protection upon booting up your computer. It is more advance than Internet Connection Firewall.


  • Regularly update to new versions of your software based firewall
  • Enable WEP (Wired Equivalent Privacy), which prevents intruders, for your wireless network


Phishing, also referred to as brand spoofing or carding, is a variation on "fishing," the idea being that bait is thrown out with the hopes that while most will ignore the bait, some will be tempted into biting.

Phishing attacks use both social engineering and technical subterfuge to steal consumers' personal identity data and financial account credentials. You can be solicited via email to go to a web site or via instant messaging and provide personal information about yourself. The way you would end up doing this is that the Phisher would pose as a reputable company or authority to trick you in to giving up personal information.

If you are suspicious about any website requesting personal information from you, investigate further before you reveal that information. If you are already a victim immediately change your username and password, contact your credit card company, let other reputable organizations know that you deal with that you are a victim of a scam. Phishing is a form of identity theft and you would have to combat this problem in the same way you would identity theft in general.


  • Delete or ignore email from people you don't know
  • Block or ignore people who instant message you requesting for personal information or sending you an unknown link
  • Do not give out your personal information such as credit card, bank account or social security number information unless you know that the website you are dealing with is reputable.

More Ways to Protect Your PC

Additional ways to keep your computer safe.

These additional security tips are design to help home users, home office workers, and small LANs to improve protection of their computer(s).
1. Backup your computer's data
2. Periodically update your operating system
3. Use strong passwords
4. Use extreme caution with email attachments
5. Use encryption software for confidentiality
6. Create a boot disk
7. Check your computer's security often

1. Backup Your Computer's Data

It is highly recommended that you make regular backups of your important computer information. You can either back up your entire computer or just selective files and folder, but whatever you decide you should back up often.

Depending on your needs you can use Tape drives, Zip drives, CD-RW, external hard drive, or a DVD-RW. ��Online backup services are available for off-site storage needs.� �A backup program is as good as it's recovery tool and make sure the program that you get also allows you to recover all of your data exactly the way you stored them. In case the worst happens, the restore tool will be the only way to get back to your lost information.

2. Periodically Update Your Operating System

Unfortunately, operating systems are not built perfect. Vulnerabilities that lead to security risks are often discovered that it becomes necessary for the operating system developer to write a patch to fix the security risk. It is up to you to regularly check the operating system company's web site to download new updates. Without these updates you are very vulnerable to an attack that exploits these security risk.

It is recommended that you download and install these patches often and check to see if your operating system provider has a piece of software that can automate this process for you. Either way, make sure it gets done.

3. Use Strong Passwords

It is important to keep your passwords safe and secure. You shouldn't give your passwords out to anyone because of potential abuse. Having different passwords for different places increases security because if one password is compromise your other information will still be safe.

When creating your passwords, it should be at least six characters minimum and be a combination of letters, numbers, and special characters. Don't make your passwords easy to guess and every 60 to 90 days, or so, consider changing your password again.

4. Use Extreme Caution with Email Attachments

The rules are don't open email attachments from an unknown person and emails that are highly suspicious. These rules hold true, but are not set in stone. Where these two rules are weakest are when you receive an email that seems like it is from someone you know or it is actually from someone you know.

Some emails are not so obvious about coming from an unknown source. The malicious creators use a form of social engineering to get you to open the attachment. The email fools you in to believing it is from someone you know, or it can have a really enticing message that peaks your interest, or it maybe have a picture or movie that makes you curious enough to open it. All have the same effect and that is getting you to open the email attachment and unleash a harmful computer virus.

Harmful email attachments can even come from someone you know with or without their knowledge. Your friend could unknowingly send you a virus attachment disguise as a text, picture, document, or movie thinking you might find the email useful or entertaining. Coming from a trusted source, you open it without thinking twice and unleash trouble.

A friend of yours may be infected with a virus that sends copies of itself to everyone in that friend 's address book. Without their knowledge, you receive an email that did come from your friend, you open it, and then the virus in turn send copies of itself to people in your address book. Such was the case of the I Love You virus around May 2000. Which caused millions of dollars worth of damage and did more than damage than just emailing copies of itself.

If an email is obviously from an unknown source and it is suspicious to you then delete it right away from your inbox. If you must open an email attachment then the safest way to do this is save the file on to your computer and run a virus scan on it before you open it. Make sure that your anti-virus program is up to date. If no virus is found then it is safe to open it.

5. Use Encryption Software for Confidentiality

If others use your computer or if you are on a network, it might be a good idea to add an extra layer of protection for your sensitive files. Encryption can provides that extra layer of protection from prying eyes.

What encryption does is make your file unreadable without a decryption key. In essence, it transforms your unscrambled information in to a scrambled, human unreadable data that needs a key to unscramble it again.

Virtual Private Networks (VPN) are commonplace and enable safe access to company files from anywhere. Accessing your company's intranet remotely via a VPN is considered the safest way to transport data between locations, as it is encrypted as well as paperless.�

Depending on which operating system you use and the level of security you need for your sensitive information, encryption may be your only solution for confidentiality. Some operating system doesn't have permission-based access of files, for example: Windows 9x. What this means is everyone can access your files that have access to your computer. With other operating systems, such as Windows XP, you establish ownership of a file where only you and others that you wish can access certain files. For a higher level of security, you establish yourself as the only owner of a file and encrypt it in case of a security breach.

6. Create a Boot Disk

A boot disk is necessary tool to have in case of a complete hard drive failure or recovery from a boot sector virus attack. Without a boot disk it will be difficult, if not impossible, to get your computer to boot up properly from a failure. The important thing to remember about a boot disk is to create one before disaster strikes. Please follow the instructions found in your operating system on how to create this important tool.

7. Check Your Computer's Security Often

A couple of times per year you should do a complete security check of your computer. This includes updating your operating system patches, updating your antivirus definitions, and updating patches for Internet Explorer, MS Office, and other frequently used programs on your PC. You can also use free online services that can search for security holes for you on your PC.

Your goal is to check to make sure that everything is running properly and you reduce the security risk as much as possible. Stay on top of your computer's security as often as you can.


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