Dealing with malicious software

Malware, or Malicious Software, is a term used to describe any software that is installed but uninvited on a person’s computer. This can be a virus or spyware that can disrupt our computer’s operation or surreptitiously spy on our computer usage. But there is another type of computer attack that can allow someone from the outside to take control of our computer and use it as they see fit without our permission.

Malicious software attacks usually are blocked by antivirus or antispyware programs installed on our computers like those from McAfee, Norton, Spybot, Adaware or others. The other type of outside attack can only be blocked by the use of a Firewall.

Each computer connected to the Internet, whether by dialup, dsl or cable, has an assigned address that the Internet uses to route information to that computer. When we request the website,, our computer sends out a request to the Internet system to be connected to the computer at CNN. The computer at CNN then sends a copy of its web page back to the address assigned to our computer. This is simple and straight forward.

However, what if someone somewhere wants to connect to our computer and possibly have access to our files or wants to use our computer in an email scheme to hide their own address? If they could find our assigned Internet address, they could access our computer without our knowledge. Is this possible? What if the outside computer simply has a computer program that generates millions of random addresses and one of those matches ours? They can get into our computer.

To stop this type of attack we use a Firewall. In its simplest form, a firewall keeps track of our Internet requests and then only allows information from the requested site to return to our computer. Anyone trying to access our computer who is uninvited cannot get past the firewall. In commercial applications, firewalls also can be programmed to filter information so no x-rated or other undesirable data can gain access to our computers.

Where do we get firewalls? Windows XP has a built in firewall and in Service Pack 2, it is turned on by default. To see if your Windows firewall is activated, click Start, Control Panel, Windows Firewall and check the settings. You can have more than one firewall running on your machine at one time. McAfee has a firewall that may come along with AOL or can be purchased separately. ZoneAlarm has a free, downloadable firewall at and others are available over the Internet. If you are using a home network and use a router, it probably also has a firewall as part of the router hardware.

To test your computer’s susceptibility to attack, go to and use their Shields Up program.

Even though the chances of a successful attack on a home machine are slight, be sure you have one or more firewalls operating on your machine just in case.

If you would like to hear more about firewalls, or other computer topics, visit “Coffee and Computers” at the Tustin Area Senior Center, 200 S. ‘C’ Street, any Friday morning starting at 9 a.m. Bring your questions or just come in and visit.

In the mean time, keep the neurons happy, synapses snapping and enjoy computing.


Dr. Art Holub is a long time resident of Tustin and teaches computer and Internet at the Tustin Area Senior Center. Visit his web site at: This column is written to address the computer adventures and concerns of older adults. If you have comments, questions or suggestions for future columns, Email HIM at:

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