Here is my problem: I was on Ubuntu LTS 16.04. I then moved to Xubuntu. However I really want to come back to Ubuntu. This is why I reboot my computer with an usb key with Ubuntu inside.
However I still have the Xubuntu desktop and menu but when I press CTRL ALT F1, it tells me that I am on Ubuntu 16.04.
If someone knows how to come back to "real" ubuntu, i would be very thankful!