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alas, it is true that the question itself is a duplicate but the answers in the other places did not work for me. So I will try again with updated info. Here is what is happening at boot. 1. Think Pad Screen(normal) 2. Gnu Grub screen with three choices: first one ubuntu something (I can't read my own notes!), second one is recovery, third one is previous ubuntu version (not normal screen). I go with the first one. BTW this screen started showing up with a Debian earth background (new and not normal). 3. Normal boot up screen black background white Ubuntu letters. 4. Running in low graphics mode (not normal). I say yes run once in low graphics. 5. Older Ubuntu version login screen shows up. I set dropdown to Ubuntu and I get my normal Ubuntu desktop back! Wow! But there are some system problems,instability, nautilus crashes, etc. What do you recommend to get back to the normal boot up sequence:1. Think pad screen. 2. Ubuntu black background, white letters. 3. Normal 12.04 Ubuntu desktop?