I initiated the recent update using the update manager. As I have a rather erratic (wireless from a tower) connection I left it running overnight.At some point it lost the connection and did not restart and hence was short of 6 packages so I allowed it to complete the partial upgrade.I downloaded and installed the missing packages (Firefox, Thunderbird, Calibre) and completed the update process.It reported some broken packages (Libre Office) which I reinstalled and all seemed satisfactory and the upgrade indicated as complete. I checked the main applications which all seem to work as expected. However I was not able to reboot. I could only log off and return to the login screen.The shutdown button on the top right of the login screen also failed to do anything.'Shutdown now" in the terminal also failed. I forced the issue with the power button!
On restart grub was functional but when I selected the latest version i was booted into the console for logging in. However "startx" failed with some issues with x configuration I think including no screens.Finally I rebooted again and returned to the previous kernel which works as normal including Xwindows and from where I write this.I probably brought this on myself with the partial upgrade but nevertheless would appreciate some suggestions as to how to undo the damage. Thanks,Colin.