HP PRINTER OFFLINE IN WINDOWS 7

First, have you ensured that the printer is working correctly, i.e. no flashing lights, paper in the tray, etc...? If that isn't the issue, do you have the correct driver installed for the printer, i.e. a W7 driver? You can also try to unplug the printer for a few seconds and then plug it back in to see if that does the trick (if it is indeed an issue with the printer itself).