HP Compaq Presario,Presario 800AP Supplementary Manual page 48

A computer virus is a program that damages or erases files or
programs. Your Notebook can become "infected" with a virus
when you open a contaminated program or file. Some signs
indicating that your Notebook may be infected include:
• Strange characters or crude statements suddenly appearing
on your screen
• Hard drive, memory, or software error messages
• Damage to files or directories for no apparent reason
• Strange responses to commands
• Sharp decrease in performance or program speed
If you suspect your Notebook has
been infected with a virus, find and
remove the virus immediately using
an anti-virus program.
After you have followed the
instructions provided by the
anti-virus program, complete
the following steps:
1. Turn off your Notebook
and leave it off for at least
30 seconds.
2. Turn on your Notebook and
rescan for the virus.