While trying to update the system using the kde4 updater applet, there were 16 updates. After clicking 'update' and entering the root password, the only thing that happened was that the update icon told me (again) that new software was available for the system. Nomatter which updates I selected (by default all are selected), this message kept appearing after approximately 5 seconds after I clicked on 'update'.

After examining /var/log/zypper, I saw that the problem was that I had debuginfo packages installed and that there were updates available for the base packages. Such instances were helpfully listed as "problems" and I was able to solve the above problem by deinstalling the debuginfo packages which were causing the problems. After deinstallation, I clicking on the updater applet again, clicking on 'update', entered the root password, and everything worked.

Could the applet not have told me the cause of the problems, or simply to look in /var/log/zypper.log? In the applet configuration, 'show notifications' is checked.