Preventing and removing viruses

Computer viruses are software programs deliberately designed to interfere with computer operation, record, corrupt or delete data, or spread themselves to other computers and throughout the Internet. Viruses often slow things down and cause other problems in the process.

Learn more about viruses and how to prevent them and remove them from your computer;

How do viruses work?
How to help prevent computer viruses
Signs of viruses: Are you infected?
How to remove a computer virus
How do I install antivirus software if I can't use my computer?
Where can I get antivirus software if I don't have it installed?
How do I keep my antivirus software up to date?
What is a software patch, and why are they important to my computer's security?

How do viruses work?
Basic viruses typically require unwary computer users to inadvertently share or send them. Some more sophisticated viruses like worms can replicate and send themselves automatically to other computers by controlling other software programs, such as an email sharing application.

Certain viruses, called Trojans, can falsely appear as a beneficial program to coax users into downloading them. Some Trojans can even provide expected results while quietly damaging your system or other networked computers at the same time.

To help avoid viruses, it is essential that you keep your computer current with the latest updates and antivirus tools, stay current about recent threats, and that you use safe computing practices when surfing the Internet, downloading files, and opening attachments. Once a virus is on your computer, its type or the method it used to get there is not as critical as removing it and preventing further infection.

Steps to avoid computer viruses
Nothing can completely guarantee the security of your computer. However, you can continue to improve your computer's security and decrease the possibility of infection by using a firewall, keeping your operating system up-to-date, maintaining a current antivirus software subscription and following safe computing best practices. Because no security method is guaranteed, it's important to back up critical files on a regular basis before you encounter a virus or other problems.

Steps to help avoid viruses:

  • Use an Internet firewall. The firewall that is built into your operating system provides a helpful defence against viruses.
  • Keep your software and operating system up to date. It’s no longer enough to just keep your operating system and browser up to date you must also keep your other applications up to date as well such as Java, Adobe flash etc. Both Windows XP and Mac OS X support automatic updates. There is also software available for your PC for regularly installing “patches” for your software. A patch is a piece of software designed to fix problems or to update a computer program or its supporting data. This includes fixing security vulnerabilities and other bugs, and improving the usability or performance.
  • Subscribe to industry standard antivirus software.
  • Never open an email attachment from someone you don't know.
  • Avoid opening an email attachment from someone you know, unless you know exactly what the attachment is. The sender may be unaware that it contains a virus. Before you open the attachment, scan it with antivirus software.

Signs of viruses: Are you infected?
After you open and run an infected program or attachment on your computer, you may not realize that you've introduced a virus right away. Here are a few signs that your computer might be infected:

  • your computer runs more slowly than normal
  • your computer stops responding or locks up often
  • your computer crashes and restarts every few minutes
  • your computer restarts on its own and then fails to run normally
  • applications on your computer don't work correctly
  • disks or disk drives are inaccessible
  • you can't print correctly
  • you see unusual error messages
  • you see distorted menus and dialog boxes.

These are common signs of infection, but they might also indicate hardware or software problems that have nothing to do with a virus. Unless you run and install industry-standard, up-to-date antivirus software on your computer, there is no way to be certain if your computer is infected with a virus or not.

How to remove a computer virus
Even for an expert, removing a virus can be a daunting task without the right tools.
Some viruses and other unwanted software (including spyware) are even designed to reinstall themselves after they have been detected and removed. Fortunately, through updating your computer and using free, trial-period or low-cost antivirus tools offered by many companies, you can help permanently remove and prevent unwanted software.

Steps to help remove a virus:

  • Enable automatic updates and install the latest updates. Windows XP and Mac OS X support automatic updates.
  • If you currently use antivirus software, visit the manufacturer's website, update it, and then perform a thorough scan of your system. If you don't currently use antivirus software, subscribe to a service and scan your system immediately.
  • If you are a windows user, you can also download, install, and run the Malicious Software Removal Tool (for Microsoft Windows XP or Windows 2000 users). Note: This tool does not prevent viruses from infecting your system, it only helps to remove existing viruses.

How do I install antivirus software if I can't use my computer?
In some cases, it might be difficult to download tools or update your system if a virus has already disabled your computer. In this case, use a friend's or other computer to download the tools to a disk, or get support from your operating system or antivirus software vendor.

Where can I get antivirus software if I don't have it installed?
If you don't have antivirus software installed, you can get it from one of several companies, including Microsoft, McAfee, Symantec or your Internet service provider.

How do I keep my antivirus software up to date?
Out-of-date antivirus software is ineffective and puts you at risk. Antivirus software relies on regular updates to help protect against the latest threats. If you aren't subscribed to these updates, your computer may be vulnerable to attacks by malicious software. Here are some tips for making sure your antivirus software stays current:

  • Purchase an annual subscription from your antivirus software company to make sure your antivirus software stays current and effective. If you have purchased a subscription, most antivirus software will update itself when you are connected to the Internet.
  • To ensure your software is up to date, open your antivirus program from the Start menu or the taskbar notification area and look for update status. If you still aren't sure if your antivirus software is up to date, contact your antivirus software provider.

What is a software patch, and why are they important to my computer’s security?

A patch is a piece of software designed to fix problems or to update a computer program or its supporting data. This includes fixing security vulnerabilities and other bugs, and improving the usability or performance. If you regularly update your applications with patches offered by the manufacturer, you can greatly increase the security of your computer.

It’s no longer enough to just keep your operating system and browser up to date you must also keep your other applications up to date as well such as Java, Adobe flash etc. Vancity strongly urges you to keep your system patches up to date. Macintosh OSX users are automatically notified of new patches. If you are a PC user, you can use free tools like Secunia, which will notify you of new patches and even automatically install them on your computer, if you wish.