Depending on how many different users use your computer, their Internet browsing and e-mail habits, and their overall sense of Computer Security, it is possible that you may end up with some very harmful and hard to identify viruses on your computer.  The first thing that most people ask themselves after they find a virus infecting their computer is: how did I get that virus?

1. You or someone using your computer visited a website that had harmful code embedded on that site and downloaded or installed infected files or malware onto your computer.  Stay away from "bad neighborhoods" on the internet that contain such malware.  Also, avoid deals "too good to be true" - usually they are decoys trying to entice innocent citizens to visit their websites so that they can infect your PC with a virus or browser hijack.

2. You or someone reading email on your computer opened an attachment that they received by email thus allowing the embedded malware file (usually an attachment in the email) to execute on your computer releasing the infected files.

3. You or someone using your computer inserted removable media such as a burned CD or DVD, USB flash drive, or memory card into your PC that contained an infected file or malware.  Once that media is inserted into your PC, the infected file(s) are granted access to your computer's hard drive and the infection now spreads to your PC.

If you have done your normal scan using your antivirus client software, but suspect there may still be something wrong or other now where infecting your computer, we highly recommend running an online virus scan.  Online virus scans are extremely effective, and can be more comprehensive than the standard scans using your antivirus client software located on your PC.  This is partly due to the fact that you can run the online scan while your computer is in safe mode, and no programs are actively running on your PC thus preventing any place for malware to hide during an active scan.

In summary, it is critical that you have a current antivirus software installed and running on your PC.  Additionally regular updates to your virus definitions need to be accomplished in addition to a regularly scheduled full scan of your computer's hard drive period this is one of the first things you should do upon purchasing a new PC.  Remember, the minute you have a live in a connection and are receiving emails, you are susceptible to Internet threats and now wear.  Often, viruses are received without the computer user having done anything wrong.  Most of viruses and malware today are spread via e-mail, often spread by automated "bots" that may have infected your friends' or family's computers and thereby taking over their e-mail address books. 

This is why it is extremely important to be judicious in your e-mail reading practices.  Do not open attachments from people or entities that you do not know, and even the attachment from friends or family may be infected if their computers have been overcome by viruses.  Lastly, watch out for online scams propagated by e-mail in which impostors are trying to solicit your username, password, personal information, bank account and financial information.