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Computer Viruses
What You Need
to Know to
Protect Yourself
 Boot-sector infectors
 Attach to the “boot sector” of a disk
Macro viruses
 Attach to documents and spreadsheets
Types of Viruses
 File infectors
 Attach themselves to programs
Other Malicious Programs
 Trojan Horses
 You run the program on purpose, but it
does something more than you thought
Worms
 Like a virus, but spread via a network
without direct human intervention
How Much Damage?
 Malignant Viruses
 Cause great damage that may or may
not be repairable
 Benign Viruses
 Annoying, but not serious
Ways Viruses Spread
 Email attachments
 Shared files
 Floppy disks
 Infected documents and infected
word processors
Important: Viruses almost never spread
between operating systems such as Mac
and Windows!
Spreading a Virus
Jake
EricChad DanielleBeckyAaron
Friend
Friend
Friend Friend
Friend
Friend
Ways to Prevent Viruses
 Install a virus scanner
 Keep it updated
 Many are free
 Set it to run automatically
Prevention (continued)
 Do not open email attachments you
were not expecting
 If downloading from internet, scan
with virus scanner before opening
 If you use Microsoft Word or Excel,
disable macros
 Keep your operating system and
programs up-to-date
Prevention (continued)
 Do not run random programs you
find on the internet
 Turn off scripting in your web
browser
 Disable auto-run features in email
programs
How Do I Know If I Have a
Virus?
 Virus checker gives a warning
 Strange messages appear
 Computer crashes more frequently
 Strange files you do not recognize start
appearing
 Files get bigger for no reason, or disk
space disappears for no reason
 Programs stop working normally
I Think I Have a Virus!
 Don’t panic!
 Stop using the computer
 Write down any strange messages
or warnings
 Do not reboot, open files, or run
programs
 Run your virus scanner
 Seek tech support help
Virus Warnings:
Real or Hoax?
 You receive a virus warning email
 Subject: “A Great Idea”
 Will ruin hard drive, sound cards, & speakers
 Lies dormant in BIOS, even after reformat -
reappears after reformat
 Antivirus webpages indicate no fix for
problem
 Please forward to as many people as you
can! A very dangerous virus!
Virus Warnings:
Real or Hoax?
Ask these common-sense questions:
 Did the warning come from a
trusted, knowledgeable source?
 Is there a link in the warning to a
site with more information?
 Is the virus listed on an antivirus or
hoax page?
 Does the warning make sense?

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Viruses novice

  • 1. Computer Viruses What You Need to Know to Protect Yourself
  • 2.  Boot-sector infectors  Attach to the “boot sector” of a disk Macro viruses  Attach to documents and spreadsheets Types of Viruses  File infectors  Attach themselves to programs
  • 3. Other Malicious Programs  Trojan Horses  You run the program on purpose, but it does something more than you thought Worms  Like a virus, but spread via a network without direct human intervention
  • 4. How Much Damage?  Malignant Viruses  Cause great damage that may or may not be repairable  Benign Viruses  Annoying, but not serious
  • 5. Ways Viruses Spread  Email attachments  Shared files  Floppy disks  Infected documents and infected word processors Important: Viruses almost never spread between operating systems such as Mac and Windows!
  • 6. Spreading a Virus Jake EricChad DanielleBeckyAaron Friend Friend Friend Friend Friend Friend
  • 7. Ways to Prevent Viruses  Install a virus scanner  Keep it updated  Many are free  Set it to run automatically
  • 8. Prevention (continued)  Do not open email attachments you were not expecting  If downloading from internet, scan with virus scanner before opening  If you use Microsoft Word or Excel, disable macros  Keep your operating system and programs up-to-date
  • 9. Prevention (continued)  Do not run random programs you find on the internet  Turn off scripting in your web browser  Disable auto-run features in email programs
  • 10. How Do I Know If I Have a Virus?  Virus checker gives a warning  Strange messages appear  Computer crashes more frequently  Strange files you do not recognize start appearing  Files get bigger for no reason, or disk space disappears for no reason  Programs stop working normally
  • 11. I Think I Have a Virus!  Don’t panic!  Stop using the computer  Write down any strange messages or warnings  Do not reboot, open files, or run programs  Run your virus scanner  Seek tech support help
  • 12. Virus Warnings: Real or Hoax?  You receive a virus warning email  Subject: “A Great Idea”  Will ruin hard drive, sound cards, & speakers  Lies dormant in BIOS, even after reformat - reappears after reformat  Antivirus webpages indicate no fix for problem  Please forward to as many people as you can! A very dangerous virus!
  • 13. Virus Warnings: Real or Hoax? Ask these common-sense questions:  Did the warning come from a trusted, knowledgeable source?  Is there a link in the warning to a site with more information?  Is the virus listed on an antivirus or hoax page?  Does the warning make sense?