Rather than amateurs working out of their parents' basement, malware creators are often part of an underworld of criminal gang, or working directly for a foreign government or intelligence agency.

After 33 years, Bernardo Quintero decided it was time to find the person who changed his life — the anonymous programmer who created a computer virus that had infected his university decades earlier.

Antivirus software is not free of errors and sometimes reports computer viruses where there are none. For this reason, the company Procolored, a manufacturer of textile printers, indignantly defended ...