El Capitan Fix! (:

I too was having the issue with scanning from my HP All in One printer using El Capitan. Downloaded this and was able to connect and start scanning right away. I actually found i like this software better then any other software i was using. The other way i was doing this was time consuming. I had to edit and recrop all the images i was scanning. This application automatically crops the images you scan. Making it significantly shorter compared to other software and printers… Really nice

(Also note if youre having issues try using USB, my HP Photosmart Premuim All in One C410A uses WPA to connect to the internet. With a new router this printer became completely outdated as it could not use Wifi anymore. So maybe USB will work better for you as well. Works great for me.)

PandaGeneral21 about HP Easy Scan