A plan should be constructed to direct action if a virus attack occurred. You should know who to go to for help and who will be able to help repair any damage. Prevention is using techniques to prevent a virus from entering a computer. Control which disks are used in a computer. A dependable method of detection is necessary to detect viruses that do pass preventive measures.
Personal observation is important.
Some signs or strange occurrences indicate the presence of a virus and should be watched for. The size of a program changes. The disk runs out of free space when it seems to have plenty. Bit errors frequently occur while running Windows. The disk drive is active when it should not be.