I own an Acer Aspire One netbook model AOA101. I have had it a couple of years. I thought the battery was dead or there was some power connection problem because the battery was not charging and the netbook only worked when plugged in.

I was close to buying a new battery when I thought to check the Acer support website. It turns out I just had to update the BIOS. The battery holds a charge again!

I thought I should post the solution here for my own records and in case anyone was having a similar problem.

Next step is conditioning the battery by charging and draining the battery. I found out I was supposed to do that while searching for a solution.