If so, you may need to restore to factory settings. You can boot from the Ubuntu CD and copy any files you want to save to a flash or external hard drive.
I have an older Compaq Presario which was working perfectly yesterday until I decided to try out a Ubuntu CD. Thought that this would be a good idea since I'm using Windows xp and as everyone knows the support for that is ending. After trying out the Ubuntu cd which seemed to work OK, I removed the CD and turned off the computer. The problem now is that the computer turns on and then immediately turns off. Sometimes I see the Compaq screen for about a second and try to press the function key for a recovery, but it never works because the computer turns off. Does anyone have any idea what went wrong because I'm completely frustrated!

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