A variety of printer conditions can cause the issue of ‘Canon printer offline’. There must be a problem with the connection. A slack wire or a USB cord. Sleep mode on the printer. The printer is currently halted. There’s a paper jam problem. The paper tray must be empty. The internet connection is slow. A virus or malware may have corrupted or damaged any essential file. Drivers and software for printers may be corrupt. After an upgrade, printer drivers no longer support the latest Windows.