To resolve the HP Printer Offline, set your default printer in Windows 10. First, in Windows' list of devices, select Printers & Scanners. Uncheck the box next to Let Windows manage my default printer if it is already checked. Additionally, select Manage after selecting the printer from the list with the same name as your printer. If there are several printer names listed, pick the one that is running or not. Lastly, select Set as default from the Manage your device menu.