I am trying to reconnect my printer to wifi after being away for 6 m onths

[LooLoo89]

Model name  HPDeskjet 4100 All-in-one printer.  I am trying to connect to wifi after being away for 6 months

[Elohi_NR]

Hi @LooLoo89,

Welcome to the HP Support Community. 

I understand that you are facing connectivity issues. I’d like to help!

To provide you with an accurate solution, I'll need a few more details:

Make sure, your printer and your device are on the same network as 2.4GHZ only. 

Use the Cancel and Wireless buttons to restore Wi-Fi setup mode.

Procedure

Press the Cancel button to ready the printer.

Press and hold the Wireless button and the Cancel button at the same time for five seconds until the Power button starts blinking.

NOTE:

Your control panel might look different than the following example, but the steps are the same.

Wait until the blue Wireless button light blinks continuously.

Within two hours, return to the app or software to find and add your printer and complete the setup.

Update Firmware

Hope this helps! Keep me posted for further assistance.
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