Viruses are inactive until the infected program is executed, or a boot record is read. Thereafter, the virus loads itself into system memory and begins to copy and spread itself. Diskettes used in a contaminated system can get infected and, in turn, transfer the virus when used in another system. A virus can also spread via programs downloaded from bulletin boards or the Internet.

To Prevent Virus Infection

•Obtain an anti-virus program and make it a habit to scan the system regularly.

•Make backup copies of all files and write-protect the disks.

•Obtain all software from reputable sources and always scan new software for any viruses prior to installing files.

If the system has been infected, find and remove the viruses using an anti-virus program. Then turn off the system for a minimum of 15 seconds to clear the virus from system RAM. You may want to rerun the anti-virus software when you turn the system back on the verify that the system is clean.

Troubleshooting checklist

Before turning on the system, make sure that:

•The power cord is connected to the AC power-in connector and an AC outlet.

•The AC outlet is supplying power.

•If you use a power strip, make sure it is turned on, and the circuit breaker is set.

•The voltage selection switch on the system power supply reflects the proper voltage.

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