HP Laserjet 100 color MFP M175nw wireless printing stopped working

[rickaustin]

A couple weeks ago my HP LaserJet 100 color MFP M175nw printer stopped showing up as an AirPrint printer. I cannot print to the printer via AirPrint from MacBook Pro, any iOS device or from my Windows 10 machine running latest OS. I have followed all ideas I could find - reset the printer config, run HP uninstall, re-install all latest HP software and no matter if I am trying to configure printer from Mac or PC - seems the printer will not connect to my wifi network. My home WiFi network is a Ubiquiti UniFi and works flawlessly with every other device in the hours (laptops, smartphones, smart speakers, IoT devices, etc.). Only thing that does not work is - well - this printer. To rule out my home WiFi network, I attempted to connect the printer to a hotspot running on my iPhone - still would not connect. Hoping someone has been here / done that and has some magic advice to help get printer working again. Thank you for any knowledge you share.

[rickaustin]

Appears the problem is with the printer logging in to my wireless network. In the Easy application running on MacBook (laptop connected to printer via USB) I can see the printer, tell it that I want to connect to wireless access point (AP) and attempt to do so. It sits and spins for a few minutes then fails. I connected an Ethernet cable to the printer and was able to connect to the printer direction via web browser. I attempt to configure wireless directly and get a slightly more useful error - failed to log in. I’m at a loss - and almost ready to do the Office Space thing to this printer. It’s a shame - the printer works fine, can print to it via Ethernet or USB, just the most used feature doesn’t work (wireless, and more specifically for me - Apple AirPrint). Any suggestions greatly appreciated.

[rickaustin · Accepted solution]

After a lot of frustrating hours I finally got the printer to work again (specifically the HP LaserJet color MFP 175nw). The unfortunate fact is that HP provides little in the way of feedback to tell you what is failing, but after a lot of experimenting, was able to finally learn that the printer was not authenticating with my home network (UniFi controller and access points). I had upgraded my UniFi hardware controller and controller firmware. Apparently the UniFi upgrade defaulted to a setting that prevented this printer from being able to authenticate and connect to wireless network (unlike 50+ other devices that continue to work fine on my home network.

The setting was "Enable legacy device support (i.e. 11b)" - that was it. Enabled this option and problem solved. Hours upon hours wasted but now I don't need to buy a new (non HP) printer. Whew - what a waste of time. Better feedback from HP software sure would have helped. Another option that was suggested in a UniFi forum was "L2 Isolation" and I tried that option first but it had no affect on the printer authenticating / connecting to network.