Off line HP Envy 5540 printer

[Judi1234]

I have all of a sudden had my printer start going off line after each print job. I have done all the diagnostics suggested and it continues to happen.  I went to HP support and bought offline warranty for year but can't seem to figure out how that will even work as when I try and contact support they say my printer doesn't exist.  

[Echo_Lake]

@Judi1234

Thank you for posting on the HP Support Community.
 

Don't worry as I'll be glad to help, to provide an accurate resolution, I need a few more details:

• Is your router dual-band enabled i.e., both 2.4GHz and 5GHz? If yes, make sure the dual-band has different SSIDs for 2.4G and 5G networks.
• What is the distance between the router and the printer?
• Are the printer and Mac connected to the same network?

This printer supports WPA encryption, check if the router is on the same encryption method. If using WEP or WPA-PSK+FT change it to WPA-PSK

In addition, perform a ping test to check the connectivity:

1. Click Applications > Utilities > Terminal.
2. type ping "IP address" and press enter

Wait until 10 pings have been performed and then press ctrl c on the keyboard and hit return. 
The results will appear. Share the ping test results.
 

The wireless status menu on your Mac should also give us quite a lot of information that would help us identify the issue. You can press and hold option-click the Wi-Fi icon and then use shift-command-5 to take the screenshot. Press the space bar when the icon turns into a camera. Share the ping test results and the screenshot with us.
 

Also, check with your Internet service provider if your router is able to forward 'Bonjour packets'.  Bonjour locates devices such as printers, other computers, and the services that those devices offer on a local network using multicast Domain Name System (mDNS) service records. The software comes built-in with Apple's macOS and iOS operating systems.
And, also refer to the article HP printer is offline or not responding by the end of the article, you will be able to isolate the issue.

Hope this helps! Keep me posted for further assistance.
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