Communication Problems OfficeJet Pro 8720 w/Mac Mojave

[DoesntJustWork]

Hi HP,

I have an HP OfficeJet Pro 8720 (model M9L75A / edited**), on the same WiFi SSID as my Mac. The Mac is an iMac Pro, running Mojave (10.14.6) fully up-to-date. I can see the 8720's IP address, and access the device's embedded web server from a browser. The EWS reports: 

   Firmware Version WMP1CN1919BR Built Date 2019-05-10

Hitting the "Check Now" button on the "Printer Updates" page gets the message "The printer is up to date. No new updates are available this time."

So, the Mac is up-to-date, and so is the firmware in the 8720. I can (and have!) power cycled the printer, both from the power switch as well as the "Printer Restart" page on the built-in web server.

I have also downloaded the latest "HP Easy Start" app to my Mac (Version 2.9.0 (188)) and run it, and it sees my device. It reports that "Essential Software" status is "Up to date" (Version 5.14.6.5), "HP Easy Scan" status is "Up to date" (Version 1.9.2.126) and "Product Help" status is "Up to date" (Version 1.0.0.5). I can also re-run the download/install cycle w/out errors.

I have enabled extended alerts for errors, warnings, and informational messages. 

In the Mac OS "Printers & Scanners" control panel, I can (and have!) removed the printer, reset the printing system, and can successfully re-install the "HP OfficeJet Pro 8720 [F5C0E5]" under "Bonjour Multifunction" with "HP OfficeJet Pro 8720 All-in-One". I've even restarted my Mac a few times.

Yet: many communication-related errors. Among them:

1) I can print successfully, sometimes. Other times, "Printing - Looking for printer"

2) If I go to "Printers & Scanners" -> "Options & Supplies" -> "Supply Levels" I get the "Gathering Information" spinner, and then "Information Not Available"

2) HP Easy Start is "Unable to communicate with the device". Same story with "HP Utility", which can see the device and its IP address yet "Unable to communicate with the selected device."

3) HP Easy Scan sees the 8720, but reports "The scanner is being used by a remote user." 

4) The "Scan" button in the "Printers & Scanners" System Preference panel brings up an eternal "Waiting for scanner..." message.

5) On the printer front panel, I can select "Scan" --> "Computer", see my computer name listed, but then I get informed that my computer isn't on or connected.

Keep in mind that at ALL TIMES the following is true:

A) My Mac is on the internet and sees everything (other printers, servers, etc) on the LAN.

B) I can bring up the HP OfficeJet Pro 8720 Embedded Web Server in a browser window on my Mac.

So it CAN'T POSSIBLY be a basic network connectivity problem. It CAN'T POSSIBLY be a software update problem, as all relevant software (firmware, HP drivers, Mac OS) are 100% up-to-date. Out of courtesy, HP, please don't suggest a software update or device restart unless you have a specific, relevant insight into this situation. All of the software version numbers are provided in this post, basic connectivity is working, and device and Mac have been restarted multiple times.

The error is somewhere higher in the stack, although I can't tell where. Got any suggestions, HP? 

[KrazyToad]

@DoesntJustWork

I understand your concerns and appreciate all your expertise and efforts in troubleshooting this issue

Please check with your Internet service provider if your router is able to forward 'Bonjour packets'. This is very important

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.

Also perform a ping test using the Mac Network Utility and let me know the results. Use the printer IP address to perform a ping test, the printer IP can be located by touching the wireless icon on the printer display or by printing a Network Configuration Page

Keep me posted

If the information I've provided was helpful, give us some reinforcement by clicking the "Solution Accepted" on this Post and it will also help other community members with similar issue.
 

[DoesntJustWork]

I think we have an existence proof for Bonjour: When I go to the Mac "Printers & Scanners" preference panel, click the "+" to add a printer, the OfficeJet Pro shows up and under "kind" it offers "Bonjour Multifunction".  Is there any way we'd have a LAN unable to properly process Bonjour that would nonetheless result in the device being visible in the "Add" dialog? Also, we have several other computer on the LAN and one other HP printer, and all the computers see that printer.

If it matters, my local router is a Ubiquiti EdgeRouter Pro, and the WiFi is on Ubiquiti AC APs. Note that I did all of this testing with both devices on the same Wifi SSID, not sure that the router even enters into the picture for local mDNS packets.

Similarly, there is no need to do a ping test, since, as I reported, I can access the built-in web server on the OfficeJet Pro. Without basic network connectivity (as would be validated by ping) the embedded web server would not be accessible.

But, yes, ping works fine. 

Any other ideas?

[KrazyToad]

@DoesntJustWork

Try using the HP Smart App for Mac and let me know if that helps

You can refer to this Link: https://support.hp.com/in-en/document/c06188214

[DoesntJustWork]

Running HP Smart doesn't help at all. It reports that "Printer offline", despite:

1) I could successfully ping the printer's IP

2) I could remove the printer in the Mac OS' System Preferences / Printers & Scanners list

3) I reset the printing system, added the OfficeJet Pro 8720 back, it showed up just fine.

4) I PRINTED TO IT, successfully

and after all of that, HP Smart thinks it's offline. 

Adding to the misery, on this go-round the printer only shows up as "Bonjour", not "Bonjour Multifunction" and thus the scanner features have disappeared. 

[KrazyToad]

@DoesntJustWork

Have you tried reinstalling the HP App?

Since you are able to print and the issue is only with HP App, try creating a new user account and check if you face the same issue on the new account

Please refer to this Link: https://support.apple.com/en-in/guide/mac-help/mtusr001/mac

[DoesntJustWork]

Have I tried reinstalling the HP Smart App? I just installed it for the first time, in response to your post. How in the world would reinstalling it help?

You are incorrect that "the issue is only with the HP Smart App" - the flaky communication with the OfficeJet interferes with many functions:

1) Frequently, the (pingable, on-the-network) printer claims to be offline, yet I can delete it from the Printers & Scanners preference pane, reset the printing system, reboot the printer, re-add it, and print. At least for a little while. That's not exactly problem-free

2) None of the informational software works reliably. That includes the "Supply Levels" in the Printers & Scanners pane, the HP Utility and the HP Smart App.

3) Scanning doesn't work, neither from the front panel "scan to computer" nor the HP Easy Scan app nor the Scan function on the system preference pane.

4) Last night, hours after doing anything that involved the printer, I got a set of four "thank you for installing HP ink" dialogs on my screen. Very bizarre.

Something is seriously wrong, and all the signs point to HP software, since the basic network communication is working perfectly. Do you have any approach to support that's not "reinstall and pray"? 

I did as you suggested and created a new user on my computer. No luck with that user, although I did get a different error message, "-9923". Can you dig up some additional information on that?

At this point, I'm of the opinion that:

  1) The HP Software is broken.

  2) You don't have a clue as to what's wrong.

  3) You don't have a fix outside of "update, reinstall, and pray"

Very disappointing. 

[KrazyToad]

@DoesntJustWork

We could try assigning a Manual IP Address for the connectivity issue

First ensure the printer has the latest firmware. Link: https://support.hp.com/in-en/document/c02919168

Next assign the Manual IP Address and check if that helps

- Print a Network Config Page from the front of the printer. Note the printer's IP address.
- Type that IP address into a browser to reveal the printer's internal settings.
- Choose the Networking tab, then Wireless along the left side, then the IPv4 tab.
- On this screen you want to set a Manual IP. You need to set an IP address outside the range that the router automatically sets (called the DHCP range). If you do not know the range, change the last set of numbers (those after the last '.') to 250
- Use 255.255.255.0 for the subnet (unless you know it is different, if so, use that)
- Enter your router's IP (on the Network Config Page) for the gateway.
- Enter 8.8.8.8 for the first DNS and 8.8.4.4 for the second DNS. This is Google DNS. 
- Click 'Apply'.

If the issue persists we can attempt a Semi Full Reset back to Factory Settings and then setup the printer again
 

[DoesntJustWork]

I did the Semi-Full Reset and re-did the printer setup, deleted and re-added the printer from the Mac side. Issue persists.

Despite the scanner not working and the HP utilities reporting to me that the printer is offline, the EWS works great. Consequently, we can conclude that IP connectivity to the printer is working fine. In addition, printing still works. So I'll decline the exercise of assigning a static IP address, as this is extraordinarily unlikely to fix anything.

Firmware: It's up-to-date. It's version WMP1CN1919BR on a M9L75A if you'd like to check.  Also, I mentioned this in my first post.

Question: when I add the printer in the system preference pane, the kind is "Bonjour Multifunction" and it offers three options in the "Use" field
     "Secure AirPrint",
     "AirPrint", and
     "HP OfficeJet Pro 8720 All-in-One"
Which of these three do you recommend?

[TEJ1602]

@DoesntJustWork

Thanks, for replying!

I would suggest you use the AirPrint option to add the printer.

Hope this helps! Keep me posted. 

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!