My HP Scanner stopped working a couple months ago, with a message that "another program has control of the scanner". I uninstalled the HP printer app all together (using the uninstall.app) in my HP folder. Everything disappeared. I went into Software Updates from the AppStore and downloaded the HP update. Now, when I open the printer settings, the ff message is displayed: "You need to install software to use this printer. To install the software, choose Software Update from the Apple menu. If the software for your printer isn’t available in Software Update, contact the manufacturer of your printer."
I can print fine (although my printer icon now has a yellow caution diagram on it), but now my HP Scan icon has a "?" and I cannot access the scanner at all.
I just want access to the drivers and I should be good to go. I can't seem to find it anywhere on the HP website to download, and Software Updates from the App Store indicate that there are not updates available.
I read your post about the scanning and driver concerns you are having with your Officejet J4550 on 10.10. As you mentioned, you are correct when you say that there are no drivers available with this older unit with the newer 10.10 OS X. Your only option to install the printer would be through an Apple Update. See the link below for all of the instructions there are: HP Printers - Installing a Mac Printer Driver Using Apple Software Update
At the end of the guide, click on the "How do I scan with the built-in driver" to see your scanning options on your Mac that will not need the HP Full Driver installed.
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