Cannot install HP845c Mepis 6 Backend error handler

I am a total novice to linux mepis. I have just installed mepis 6. Works fine, but there appears to be a problem installing the printer (KDE print add printer wizard) no printers are listed under backend selection. All options are greyed out except 'other printer type'
I eventually found the CUPS web page, but when I followed the add printer directions, I got 'backend error handler' What should I do?? Please assume zero knowledge of using the command line