What are the symptoms applying to VIRUS- infestation?

The following are the sympotoms that refer to a VIRUS infestation:

• It takes longer than normal to open a file and run a program;

• Due to the limited amount of space available, the speed has been slowed;

• Displaying unwanted messages that are inconsistent with the works when the system runs;

• A software takes longer to install than usual;

• Running files take up more space;

• The computer shuts down during booting or workhours;

• File names are substituted with garbled labels.