Worked Only Once then quit

I obtained the app as a suggestion from the HP Support page after I decided to give up on the regular instructions and tutorials for HP’s own scanning software for HP Deskjet 2542, (less than a year old). I could not find instructions as to how to create a pdf with more than one page. I needed to scan 26 pages to one pdf file and none of the instrucitons on the HP support page indicated how to do that. But this app promised to be able to do that and it the preview page seemed to have understandable instructions. So I “downloaded it” (got if from the app store) and proceeded to scan 26 pages successfully. I rejoyced! But I have another 26 page document to scan. Trouble ahead! I followed the same instructions but after clicking on “Scan” I received an error message: “Scanner reported an error. HP Deskjet 2540 series is currently unavailable. Please check if itis turned on and connected, or try again later.” How disappointing! I am sitting beside the HP Deskjet 2540 and it IS available. No one else is using it. It IS connected and turned on (print function works well.)
The App page within the APP store contains no support except a link to the general HP support web page where the first question is what sort of product you are using. I give up. So: Bad rating: Only works once and then produces uninteligible error message. No effective support. Don’t bother with it.

Toronto Star Reader about HP Easy Scan, v1.4.0