Thats a password error if i'm not mistaken
Go into expert menu and do a full box reset and use the standard Root/dreambox username and password to get back into the box.
You will then have to do a complete setup again unless you have got your channels backed up
In all honesty i'd go for another image while your at it as i've never found the Pli Images that good.
I'd go for the latest Boxman CVS image in flash and using flash wizard put something like S.I.F 1.9.3 or Nabilosat Darkstar on USB. You could even put Pli back on and swap between several images to see which ones you prefer
Nano