Can't fully connect my LaserJet M1120n on Windows 8

I am trying to install a LaserJet M1120N on Windows 8 64 bit. So far, it only prints when connected by USB (but doesn't scan). It is not seen when connected by Ethernet, although it is then visible using a browser and providing its IP number.

I installed the HP Scan And Print program and provided it with this IP number of the printer, but it couldn't see it either. What should I do now?

Thanks!