I have just upgraded my Ubuntu 15.10 64 bit computer to 16.04. I was initially prompted to do this via a message under the Unity graphical front end but got the message
Could not determine the upgrade. I looked though a few previous questions posted on this site and tried upgrading via these three commands:
sudo apt-get update –fix-missing sudo apt-get upgrade sudo update-manager -d
However after doing all of this the 'About this computer' pull-down system window shows the operating system as still being 15.10 whereas the command (issued via a terminal):
shows that it is 16.04. Also, when I enter the command:
I get 7.3.3 and not 7.4 which, I understand, is supposed to be the updated version with Ubuntu 16.04. I ran Synaptic Package Manager but this says that that 7.3.3 is the most recent version. It appears that I can ask the Ubuntu Software Center to install Unity version 8 but I have not done this because I think that there may be an underlying problem.
In summary, it seems that I have a mix of 16.04 and 15.10 and if anyone can suggest how to resolve this I would be grateful.