I have ubuntu 13.10 installed. Unity does not display correctly making using the pc useless. It shows the apps but they are "whited" out. Also my hp5550 deskjet printer has suddenly stopped printing. On the print window it shows the message "rendering completed". I tried sudo apt-get remove hplip followed by sudo apt-get install hplip but the fault still remains. Any help would be appreciated. The printer uses usb.