What happens if I don't activate Windows?

The Windows activation process is used to filter out any pirated copies of the operating system and will either slow down Windows or stop it from functioning on the computer. The actual process varies according to the type of Windows operating system installed on the computer.

The Windows XP operating system becomes disabled if it is not activated within 30 days of a user receiving the notification. Later versions, such as Windows Vista, 7 and 8, limit the functions a user can access. Windows 8, for example, prevents any of the personal settings from being changed, while Widows 7 and Vista only provide updates for the most critical parts of the operating system.