HP 2820/2840 Print and Scan on Mac OS X Lion

Question: I upgraded my iMac from Snow Leopard to Lion. My HP Color Laserjet 2840 prints but I can’t scan from the device any longer. The HP Director is grayed out. I found your post about HP 2820 scanning with Snow Leopard. Do you have an update? Answer: Previous post on how to force Mac OX X Snow Leopard to print and scan with HP 2820/2840 network printer is here: Scan and print with HP 2820/2840 on OS X (Snow Leopard) In that post all the links and steps are valid for Lion but… scan is no longer supported on Lion and Mountain Lion by HP. You may try the following workaround at your own risk but there are no guarantees it will work on your machine: 1. Get Apple printer drivers for Lion. If you don’t find it download from apple.com. 2. Find HP’s latest drivers. Check out this link for download: LJMFP28x0OSX10.5Update-v8.2.dmg. 3. Switch on your printer. Check out network connections. Install HP’s package and restart your machine. 4. Uninstall the HP 2820/2840 driver from your machine you have just installed. Find System Preferences -> Print & Scan -> Use – to remove driver from the list. Install the Apple’s printer package. 5. Use System Preferences or HP Setup Assistant to discover and/or configure your network printer. You may need to manually add your network printer. Quit from the Assistant. Open HP Director and check out configuration. If you don’t find the HP Setup Assistant, use the following command in the Terminal Window:
sudo /Applications/HP\ LaserJet\ Software/HP\ Setup\ Assistant.app/Contents/MacOS/HP\ Setup\ Assistant
If you have upgraded your OS and hp_color_lj_2800_series.kext (kernel extension file) is available after your previous HP 2840 driver installation process than you can execute these commands to repair broken access rights in the System/Library/Extensions path:
cd /System/Library/Extensions
sudo chown -R root:wheel hp_color_lj_2800_series.kext
sudo chmod -R g-w,a-w hp_color_lj_2800_series.kext
Notes: OS X removes kernel extensions, like old hp kext files, that don’t conform to the latest standards during installation. If you can not find this kext file in the /System/Library/Extensions folder try these steps: 1. Open the folder /System/Library/Extensions in your Finder and start the HP installer again. 2. When the newly installed .kext appears there for a few seconds, copy it quickly to another folder (such as to Desktop) because it will be deleted by the operating system soon. 3. Then, after the installation, copy the kext file back into the /System/Library/Extensions folder manually. HP installer doesn’t work properly under Mountain Lion. You need to use a Lion or Snow Leopard machine or a bit of a hack with a USB stick with Lion or Snow Leopard installed on it to run the HP package on an old OS, and after a successful installation there, copy the HP files to the new Mountain Lion machine (or partition). Look for these folders: /Applications/HP LaserJet Software, /Library/Application Support/hp, /Library/Image Capture/TWAIN Data Sources. If yo do not understand these words please do nothing. Call an expert before you undeliberately damage your OS X installation and data files.