Why does my scanner report an infection only sometimes?

There are circumstances where part of a virus exists in RAM without being active. If your scanner occasionally reports a virus in memory, it could be due to the operating system buffering diskette reads or harmlessly keeping disk contents that include a virus in memory, or after running another scanner, there may be scan strings left (again harmlessly) in memory. These are known as GHOST POSITIVE alerts (see C5 for more details).