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PC Security FAQ

This FAQ covers issues relating to online PC security, which we are often asked & is meant to assist our clients in developing safe online habits & secure PCs

Q - I've heard about firewalls - what is it & should I have one?

A - A firewall is a piece of software (there are also hardware based firewalls), designed to keep intruders out of your system coming from online or network connected computers. The firewall is generally set up to allow data to go out from your PC, to the destination of your choice & then retrieve whatever the return data is (i.e. calling up a web page) & prevent unsolicited material or entry into your computer (i.e. someone trying to access your personal files). Mac OS X & Windows XP both have inbuilt firewall software, while there are alternatives. For Mac & Windows machines, Norton Internet Security is available, plus there are numerous other products. For older Windows systems, probably the best known firewall product would be Zone Alarm - see for more information

Installing or activating a firewall is good protection against all but the most determined system trespassers. More advanced users can custom configure their firewall software to allow or deny entry for various software which may need access to 'blocked ports' that the firewall has closed for security reasons - a good example of software that may need additional opened ports is ICQ. Many problems with Internet or specific software can be traced to incorrectly configured firewall software - if you seem unable to downlad email despite being able to viw web pages, there is a chance that your firewall is blocking your email program's attempts to download email.

Q - How do I protect my computer against viruses?

A - Good anti-virus software is readily available on the Internet for download, or commercially available software can be purchased at almost any computer retail store. While you may have purchased an anti-virus program, unless you keep it's virus definitions database (a file which the anti-virus software checks suspected viruses against) up to date, your system can easily be infected by viruses which have been made since the last virus update. Norton Antivirus, PC-Cillin or McAffee are probably the best known commercial applications, while a very effective free solution is Grisoft's AVG (a commercial paid version is also available) - see for more information.

The most common way that people's machines become infected is by opening virus files which are attached to email. A common ploy of viruses is to appear as though they have been sent by someone you know or trust (such as Microsoft) Ensuring that your anti-virus program is up to date should protect your machine from any viruses which may enter the machine - of course, not opening attachments unless they have been scanned is also good practice. Often, viruses can also be installed alongside other software that has been downloaded. If your computer seems to be running especially slowly all of a sudden, it's a good possibility that your machine has become infected with a virus. Good information on virus removal as well as virus removal tools can be found at

Q - My computer keeps dialling out to unknown numbers, what's going on?

A - There's a good chance that in downloading a piece of software, you have encountered what is called a dialler - this is a piece of software which often changes or creates a new dial-up connection & causes your computer to dial up a different internet connection, often to a high-cost long distance number or special service number. A variation of the dialler can also change the home-page settings on your web browser & have other effects. See also the virus question & spyware question. If you think your system may have been infected with a dialer, you should carefully check your phone bill, as the cost of the phone calls can be exceptionally high.

Q - How can I cut down junk email or spam?

A - One of the easiest ways to eradicate spam is to avoid posting your email address to web page message boards, forums or newsgroups. there are automated 'spambots' which search web pages & harvest email addresses to then add to mailing lists & post out spam. One of the ways to combat this is to post your email address in a format like so, with instructions as to how to send email to you: (please remove nospam from the front of this address to send me email)

Most current email software also incorporates filtering for junk email & good Internet Service providers are beginning to offer dual spam & virus filtering for their clients, while there are also commercial applications such as Norton Anti-Spam to help reduce the amount of junk mail.

Q - My Internet connection is very slow or keeps dropping out - what's the problem?

A - There are a myriad of different reasons for dial-up internet connection problems. Some of the primary reasons include call-waiting being enabled, which will disconnect you if there is an incoming phone call, faults in the phone line such as static, virus infection on your computer, problems at your Internet Service Provider or even software problems. In short, there is no one reason why your Internet connection is slow or is dropping out, but the above will certainly help to narrow down whatever problems you may be experiencing.

Q - My Internet bill has become very expensive all of a sudden - what could be causing excessive usage?

A - One of the most likely causes is that you may have installed a music or file sharing application. there are a huge variety of software applications you can install to share files with friends or other people across the Internet. Many people are unaware that all the time you are using this software, a large amount of data is being transferred that you may be unaware of, because the default settings for these programs allow other people to download shared files from your system, such as music you may have downloaded. Additionally, other software is sometimes unwittingly installed alongside these programs owing to hidden programs, known as 'spyware', which we have covered below. There are numerous file sharing applications available - for Windows, Kazaa or Limewire are probably the best known, with Limewire also available for Macintosh, while an excellent file sharing program for Macintosh is Poisoned

Q - I've heard about something called spyware, what is it?

A - there are numerous types of so-called 'spyware' programs. These are generally fairly innocuous programs which can often be installed unknown to you alongside other programs such as Kazaa or other file sharing software. There are however, some spayware programs which can operate completely unseen. Particularly malicious spyware can capture password or personal information as you enter them, sending those details off to unknown recipients or perhaps allowing access to files on your computer. There are numerous spyware detection & removal applications, such as Ad-Aware

If you have other questions you'd like added to this page, please email
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