Ubuntu 16.04 and HP OfficeJetPro 7740

[beppe_rm]

Hi all,

I'm not be able to properly use hp 7740; it doesn't print on A3 (I put the A3 paper on tray #2) and the scanned page is shorter then normal; I installed hplip-3.17.19 ( following https://h30434.www3.hp.com/t5/Scanni...n/td-p/5881581 ) and use Ubuntu 16.04 lts; could anyone help me?

Thanks

[beppe_rm]

It needs to change the permissions to ppd files, but still hp-doctor reveals one error of plugins:

"Checking for HP Properitery Plugin's....
No plug-in printers are configured"

but if I make hp-plugin it doesn't work again, and I have to reinstall hplip-3.17.10 from the beginning.

What can I do?
Thanks