I had my power adapter plugged into my laptop, as normal, but the power indicator light did not come on as normal when I plugged it in before I opened the lid. It works in battery mode when I open the lid. My Toshiba PC Health monitor tells me the battery is "good." I'm using it now and it seems OK in battery mode. And yes, I checked the unit and cords--look fine. Power is on. There are no "stupid" mistakes on my part. Is there any way to check the "power adapter" in the laptop (laptop side--I don't mean the external one) using the Win 8 OS? I know this is probably a "hardware" problem but I figured I see if I could get any information from Windows 8 about the issue. I went into the device manager and checked the properties of Microsoft AC Adapter and Compliant control method battery, both under the "Batteries" section. I checked what seemed could be related to power under System Devices, and all say "This device is working properly." It is like the computer doesn't recognize it is plugged in to an AC source. If anyone knows a Win 8 method to check anything before I try to order an adapter or so forth, it would be appreciated. Thanks.