Fixing HP LaserJet 600 M602 with error 49.38.03
New HP LaserJets are like Windows PCs. Operating system is bloated and buggy. Recently I had to fix HP LaserJet 600 M602 that said "49.38.03 error, turn power off then on" each time you tried to access network settings via menu - and via ethernet it was completely dead. To fix this turn printer on, press (X) button when all three leds on front illuminate, login as admin, clean entire disk and reload firmware from USB stick.