I am using acer laptop with window 7 basic. As and when it is on and window is displayed, it starts to type '11111111111111111' without any stop.
Any body with the solution.
Assuming you have tried looking for a stuck key, I can share that at our company we had a bunch of Acer laptops (Aspire 5 series) with a similiar defect. The keyboard seemed to send a neverending string of "1"s. Pressing "1" actually stops this but after releasing the key the behaviour returns.
This seems to be a problem not with the keyboard but with the firmware. Our solution was to return them and let Acer handle the issue -- which they did in about 4 weeks time.
Probably key 1 is stuck. Take the keyboard apart, and check. If the key is stuck, fix it; otherwise, disconnect the key to see whether the problem is in the physical key or in the wiring.
Tap Hard on key 1 to see if its stuck.
As its laptop, Taking Keyboard Apart Wont Help. See on the net how to open key for your specific keyboard type.