AC Adapter Cannot be determined

Hello, 

I am having a problem for few months now and it is getting quiet annoying.

I have a Dell Inspiron N411Z

I had it for few years but started using it last year. I had no problems until the beginning of this year. First, I started getting messages that my AC Adapter cannot be recognized but I was able to fix it by unplugging the charger and plugging again until my old battery got spoiled and I had to purchase another new battery from Dell. I still have the problem with the adapter with the new battery which has been replaced twice and it's giving me messages that it's not determined. 

I tried everything. From unplugging the charger. Updating BIOS, getting a new charger but the problem is still there.

I am very frustrated about this problem and I hope to find a solution that would fix it for good.

Thanks