Y2K bug

The Y2K bug, also known as the Millennium Bug, (AUDIO: The Last Line of Defence) was a discrepancy in the clocks of 20th century Earth computers.

In 1999, the British government worked to resolve the Y2K bug problem, but had a military force under General Randall ready to handle any chaos that the "bug" did cause. The Voracians attempted to use the glitch to take over Earth using their sentient program Voractyll, but were stopped by the Fourth Doctor. (PROSE: Millennium Shock)

David Harker thought Ashley Chapel was going to use the Millennium Codex to manipulate the Y2K bug and steal money from banks, and wanted to be part of the scheme. (PROSE: Millennial Rites)