My laptop is 4420-5963 acer extensa... About a month and half back it suddenly refused to on. When you pressed the on buttn it would show the green light which would flicker then the laptop would go off without actually powering up. Ishowed it around and sme peole said it has a circuit problem some said its mother boards fried. But today I turned it on and it powered up normally but then the keyboard wasn't functionong at all yet the device manager said device working properly. I put it off and chargde it since the batt was low. It has refused to on again and has the same pattern as a month and half back. Help I really love my laptop.

You need to have it professionally looked at as something is going and or gone and it won't just fix itself.

What OS? If it is Windows have you tried starting in safe mode?