I kept getting errors about the system being unable to mount an MTP device and have resorted to some ridiculous things trying to get content off devices. Under KDE, Dolphin never seemed to work to get things via MTP (Media Transfer Protocol), but Konqueror did so I just used that. Yesterday I did a search for ‘ubuntu unable to mount nokia unable to open mtp device‘ hoping to find something that would help and I did on AskUbuntu!

sudo apt-get install mtpfs