Comment 3 for bug 1476011

Sourceforge site is down (http://sourceforge.net/blog/sourceforge-infrastructure-and-service-restoration/) and unfortunately hp-plugin utility is not able to fetch the plugin.conf from sorceforge site.
Can you directly download the plugin files from here:
https://www.openprinting.org/download/printdriver/auxfiles/HP/plugins/hplip-3.15.2-plugin.run
https://www.openprinting.org/download/printdriver/auxfiles/HP/plugins/hplip-3.15.2-plugin.run.asc

To install the plugin file you can run command 'sudo sh hplip-3.15.2-plugin.run' in terminal or you can run command 'sudo hp-plugin' in terminal and choose the second option to manually select the hplip-3.15.2-plugin.run file and install.

Run command 'hp-setup' to configure the print queue.