I've installed new version of Ubuntu on my laptop without any issue using the LiveCD. But on my desktop, weird things happen:
During the 1st try booting with the LiveCD on my desktop, my 2 year old child just hit the keyboard, and after several error messages the desktop loaded and I've been able to test Oneiric. But I wanted to redo a boot before installing Oneiric to avoid mistakes.
So during the 2nd time I tried to boot with the LiveCD, I couldn't access to the point where I can choose to test or install.
Before trying a 3rd time, I've "cleaned the system" from System Parameter > System. But after that I'm still not able to access to the point where I can choose to test or install. Now it stops all the time on a black screen.
I do not understand why several boot attempts with same CD have several results.
So I wonder if the state of my current installation can affect re-booting with my LiveCD ?