Cannot initiate scan from OJ x476dw to MacBook Pro Touch Bar running Mojave

[richard-liu]

I just recently updated to macOS 10.14.6 Mojave from 10.13.6 High Sierra.  For as long as I have had my OfficeJet X476dw I have been initiating scans from the printer control panel that are then saved on the computer.  On Mojave, this procedure results in the following error message on the computer:

"This workflow contains 'Scan Items from HP Devices', which is provided by a third party.  Third party actions must be explicitly enabled."

The message provides not hint how to "explicitly enable" what.  I'm hoping that somebody here can help.  I do not believe that what is often offered as a solution on these boards is what I need, namely HP Easy Scan.  That requires that I run between my computer and the printer and, in particular, start the app on the computer.  I want to start the scan from the printer control panel, as I have done in previous versions of macOS and not have to do anything on the computer except find the scanned documents saved there.

[ShlomiL]

Hi,

From your Applications folder open the HP Easy Scan app.

Click the top HP Easy Scan menu item and then click Check for Updates.

Install any available update for the app.

Next, open System Preferences > Printers & Scanners and double-click your printer.

Click the Settings button, open the Utility tab and then click on Open Utility.

Under Scan click Manage Scan to Computer and ensure the feature is enabled.

If that doesn't help, from your Applications folder or its HP sub-folder delete any existing HP Scan or HP Easy Scan application, delete it by moving it to trash, then empty the trash.

Next, install the latest HP Easy Scan below, it will be installed within the Applications folder:
http://ftp.hp.com/pub/softlib/software12/HP_Quick_Start/osx/Installations/Essentials/hp-easy-scan-1_...

If you experience any further issues, ensure the latest software is installed by following HP Easy Start below:
http://ftp.hp.com/pub/softlib/software12/HP_Quick_Start/osx/Applications/HP_Easy_Start.app.zip

Finally, ensure your drivers are up to date by clicking the Apple icon, select About this Mac and then press Software Update.
Click Store on the top menu bar, click Reload Page, click Update All if any updated are available.

Regards,
Shlomi

[richard-liu]

Thanks, ShlomiL.

I have HP Scan in a folder named "Hewlett Packard" in the Applications folder; I do not have HP Easy Scan.  When I run the HP Utility in the same folder I see that Scan to Computer is enabled and, as I said, when initiated from the MFP's control panel the process begins to run on the computer, but produces the error message, "NSWindows ...".  I have read many recent threads devoted to the problem of scanning to a Mac from an MFP, but I have not found one that confirms that your advice solves the problem.  In fact, if I recall correctly, if the problem could not be fixed merely by enabling Scan to Computer in HP Utility, it just could not be solved.

Can you point me to a thread where, essentially, replacing HP Scan by HP Easy Scan and ensuring that Scan to Computer is enabled in the HP Utility -- I believe that that's essentially what you are recommending -- solved the scan-to-Mojave (let's call it that) problem, or explain what this does that fixes the problem, e. g., does it replace HP Automator workflows that on longer work in Mojave?  I don't mean to be rude or ungrateful, but I have read threads that document making the problem worse, e. g., after trashing and reinstalling a driver and connecting over AirPrint instead of wireless  printing no longer worked.

[richard-liu · Accepted solution]

OK, here is what I did that seems to solve the problem.

Problem:  Scan to Computer from the control panel of HP MFP does not work.  A process begins to run on the chosen computer but ends with either the error message, This workflow contains "Scan Items from HP Devices", which is provided by a third party.  Third-party actions must be explicitly enabled, or, if third-party actions have been enabled, Scan failed.  The action "Scan Items from HP Devices" encountered an error:  "NSWindow drag regions should only be invalidated on the Main Thread".

Remark:  Third-party actions can be enabled in Automator.  Run Automator from the Applications folder, click its name in the System menu bar, select "Third-Party Automator Actions..." from the drop-down list and follow through.  Some Adobe apps require third-party apps to be enabled, so it is possible that that has already been done by another person and/or on another occasion, and with respect to the problem at hand, the first message never appears, only the second.

Solution:  The following is an adaptation of ShlomiL's advice above.  I describe exactly what I did that worked and omit his/her recommendations in case something does not work.  I did not try anything that did not work.

1. Download HP Easy Scan from http://ftp.hp.com/pub/softlib/software12/HP_Quick_Start/osx/Installations/Essentials/hp-easy-scan-1_... and install it.  It will be installed in the Applications folder, but not in any folders that might exist there containing other HP apps, e. g., not in one labeled "Hewlett Packard" (my case) or "HP" (explanation for this case below).
2. Check that the app works by executing it and making a test scan.  
   Remark:   I cannot make a recommendation for the case that it does not, since it worked for me.  In that case, it would probably be best to follow ShlomiL's recommendation above.
3. Ensure in HP Utility | Scan to Computer that Scan to Computer is enabled.
   Remark:  I recalled seeing an alias to this app in the "Hewlett Packard" folder in Applications; however I could no longer find such a folder there.  Instead, there was one called "HP" that contained, inter alia, everything that was in "Hewlett Packard" plus a second alias to HP Utility.
4. Check that Scan to Computer now works from the MFP.
   Remark:  If not, see my remark for step 2.
5. Clean up.
   1. Trash the old HP Scan app in the "HP" folder in Applications and empty Trash.
      Remark:  It would be prudent to ensure that Time Machine has previously backed it up; however, scanning, whether initiated at the MFP control panel or on the Mac, seemed unaffected.
   2. Move HP Easy Scan into the "HP" folder.
      Remark:  Except for having to remember the new location of the app, this bit of tidiness seemed to have no adverse effect on scanning.

Remark:  I looked into the HP Easy Scan.app contents.  It seems not to address the problems to which the error messages above pertain, perhaps it does not even use Automator actions (see https://www.computerworld.com/article/3142666/does-apple-really-want-to-kill-automator-applescript.h...).  I am not sure I would recommend replacing HP Scan by HP Easy Scan on, say, a machine running macOS 10.13 that is not exhibiting some ambivalence towards Scan to Computer.

[richard-liu]

Very important addendum to solution:  If you enabled third-party Automator actions to solve the problem about which the first error message above complains, remember to disable them!