I'm having much the same problems after starting to use debian 9 and trying to install my HP Color LaserJet CP1217 using hplip-3.19.3.run. The printer used to work perfectly well with OpenSUSE, and still does with Microsoft. I had various problems installing HPLIP, but seemed to succeed eventually in getting as far as the binary plugin, apparently without which I've printed in black and white but not colour, so have been reluctant to go back to the beginning. I comment apparently because, like Cristina, I keep getting the message that my plug-in installation was successful, only to be told immediately that I should run 'hp-plugin' as normal user to install plug-ins.
I'm having much the same problems after starting to use debian 9 and trying to install my HP Color LaserJet CP1217 using hplip-3.19.3.run. The printer used to work perfectly well with OpenSUSE, and still does with Microsoft. I had various problems installing HPLIP, but seemed to succeed eventually in getting as far as the binary plugin, apparently without which I've printed in black and white but not colour, so have been reluctant to go back to the beginning. I comment apparently because, like Cristina, I keep getting the message that my plug-in installation was successful, only to be told immediately that I should run 'hp-plugin' as normal user to install plug-ins.