To repair HP 2600 Printer Offline, first detach the USB cable and reconnect it to the Mac. After that, turn off the printer and wait a few moments. Then, after a few minutes, turn on the printer. The printer may create some noise while printing the papers in the early stages. Before starting, the printer should be turned off and silent. Additionally, reconnect the USB cable after a few seconds. If the printer begins to print, wait until it is finished before proceeding.