I have an HP Pavilion 9000 that was working just fine. We powered it down for the day and when we went to start it up the next day it would not start. Blue light is lit where power supply plugs into laptop. However when we attempt to start the laptop the keyboard lights come on for just a second or two and then the unit turns off. The blue power indicator on the front of the laptop does not come on or if it does only does so briefly and then goes out. Any ideas?

SOURCE: HP Pavilion ze5300 laptop/ Charge light on, when I try to power up it goes out and I have to reset to get light back. No boot

can you boot with the AC adapter? maybe the battery is completely dead.

SOURCE: System shuts down

Hi labiancad

Were you able to see if all of the fans are working ?

Is there any of the LED's on the Projector flickering and what colour if they are ?

SOURCE: Keyboard Problem

To activate StickyKeys
1.
Press the Shift key five times. A dialog box opens with instructions on how to set up the StickyKeys feature.
2.
If you click OK, an icon (a group of squares) appears in the notification area.
To turn off StickyKeys, press the Shift key five times.
Hope this helps you......
George

SOURCE: C500 Laptop won't come on power button just flashes

Have you tried attaching an external monitor when the LCD screen is disconnected from the motherboard? this connector is located under the keyboard strip – a piece of plastic just above the keyboard.
If it works, this way, then the video cable isn’t seated properly in the connector on the back of the screen. Plugging the video cable back in should fix the problem.
I don’t know how comfortable you are with taking apart laptops but I think that this information could be useful for you.
Source: http://www.asklaptopfreak.com/laptop-notebook-help/2006/08/08/laptop-powers-on-and-shuts-off-immediately/

SOURCE: Compaq Presario V3500. Power up - 4 beeps and flash power light.

Try to ask the company what is happening