Install a QNAP network HP C5280 printer on Windows 8

Thank you Mr MS for not including the HP C52xx driver into W8.
Download the mostly useless HP software for this printer (362MB!): you will find it easily with Google on the HP website.
Open the HP .exe in WinRAR, and uncompress it.

Goto Panneau de configuration

Then goto Materiel et audio, then "Peripheriques et imprimantes"

Then click on "Ajouter une imprimante"

Then don't let the search finish and click the "L'imprimante que je veux n'est pas repertoriee" link

Enter the name of the QNAP printer:
http://192.168.1.102:631/printers/qnapPR3
then click on "Suivant"

Then select the driver from disk. For this, in HP directory, go into prn_x86 (prn_x64) and select prnhp003.inf
Throw away all the HP bloatware.