Hey There, I am Anna Carter. If you encounter that HP Printer keeps going offline, understand why it happens. The primary reason will be something to do with the power line. Many experts suggest, when the connection between the printer and the power-line is loose, you get an offline error. Hence it is wise to remove the power line of the printer from the socket. Then wait for 60 seconds or so and then re-plug it again. Switch on the printer.