Most printers generally do not work offline, although some with a copy function may copy when offline. A printer that is offline is either not connected to a computer or not recognized by the computer and is unable to communicate or receive print commands from the device.
A printer may appear offline if it has become disconnected, entered sleep or stand-by mode or if the drivers have become corrupted. Other reasons for a printer appearing offline include problems with the printer heads, interrupted power supplies and lack of available memory.
Solutions for some of these problems are as simple as checking the connections and ensuring the device is powered on. Restarting the printer and computer solves many problems. The user may also need to install printer drivers or firmware updates or replace ink cartridges and printer heads.