Asus EEE PC 1005HA battery not being detected

"Here's something else to try:

1) Start the Eee PC up with the battery in and the AC adapter plugged in
2) Open up Power Options in Windows. In my case, the battery reads 100%
3) Remove the battery
4) Wait a minute or two and plug the battery back in

Doing this will hopefully make the hardware recognize the battery again, and it should appear as discharged in the Power Options.

It seems that many people are having this issue, which comes down to a defective battery. If the above solution doesn't work, you might just have to RMA the laptop.

Solution source"

"Most ASUS EEE PC have a reset button (use a pin) at the bottom. Might be hidden under some sticker though. Try it.

In the image below you'll see the tiny hole at the right-hand underside.

If this doesn't help, disconnect all power sources (AC adapter AND battery), press the power button to completely discharge the EEE PC, reconnect power and try again."