2.It shuts down unexpectedly or crashes frequently.
3.It experiences memory problems or runs out of disc space.
4.Unusual files or directories appear on your system.
5.Strange messages appear on your screen.
Viruses, worms, Trojan horses, botnets, malware and spyware are human-made software programs created specifically to wreak mischief on personal computers and networks. The chance of contracting one of these malicious programs over the Internet has increased dramatically. Unless you exercise great caution or routinely run anti-virus software, your computer will almost certainly become infected. Typically, you get a virus by opening infected e-mail attachments or downloading and installing infected software.
The Good, the Bad and the Ugly
Some viruses are relatively harmless to individuals. They just attach
themselves to outgoing messages and e-mail themselves to all the contacts
listed in your address book. The sudden flood of e-mail overwhelms mail
servers, causing the system to crash.
Other viruses are more destructive and may lie dormant until a certain
date. Then they spring to life to do their dirty deeds. Sometimes a strange
message appears on your screen, or data and programs may be modified.
In the worst case, all the files on your hard drive may be wiped out.
These pernicious programs start on one computer, then replicate quickly,
infecting other computers around the world.
In 1988 a student at Cornell University sent out a virus out by accident,
infecting more than 6,000 computers in minutes, nearly bringing the Internet
to its knees. The "I Love You" virus caused over $1 billion USD
in lost productivity as it crippled e-mail systems worldwide in 2000. And a worm called Conficker hobbled 15 million computers in 2008 and continues to do damage.
Inoculate Your Computer
If you download and run software from the Internet or receive e-mail attachments,
protect yourself by using anti-virus programs to scan attachments and downloaded programs to alert you of infection. The software also scans your hard drive periodically, searching for rogue viruses and deleting them.
Run anti-virus software and configure it to automatically download updates.
NOT OPEN an e-mail attachment unless you know the sender. To be completely safe, scan the attachment with anti-virus software BEFORE you open it.
you receive a suspicious message, delete it immediately from your
Inbox. Next, open the Deleted Mail folder and delete the message
again to permanently remove it.
back up your files. If your system
becomes infected, you won't lose your valuable data.
The two most popular programs are from McAfee.com
and Symantec. You can purchase and
download the software from their websites. Both offer regular updates to handle
newly discovered viruses.