My Problem: had the Canon S300 running perfekt on USB-device of Fritzbox.
After tryin to print a pdf-file, there was suddenly no more "normal" printer, but only a "CupsPDF"-printer.
When I tried to install a new printer over webinterface, everything stopped with the start-window for CUPS: no new window opened. So I typed the localhost:631 to the addressbar and got the webinterface.
But now every trial of installing the before perfectly running CanonS300 end up with the "ADMIN error server-error-internal-error"-window.
??
Anybody out there with some handyhelp to me? Would be very pleased!!

Thanks so far for reading my post..
bjoenn
Puppy 431_de; Fritzbox 7170;