ever ran into a (x)sane-message claiming an error to scan via hplip like this?
"failed to open device hpaio:/net/HP_LaserJet_M1522nf_MFP?ip=192.168.12.34"
well, it turned out that on my system (currently ubuntu 9.04) HPLIP was installed fine and even downloading and installing HP’s proprietary code for scanning was done right by HPLIP. what actually was missing is a link on “libhpmud.so”, issuing the following command solved my problem and everything works fine now:
sudo /bin/ln -s /usr/lib/libhpmud.so.0 /usr/lib/libhpmud.so
for more information, see launchpad bug nr 357801