I've been through same problem, that i plugged in charger but,
it shows message that , plugged in, not chargingi've all updates installed,
after seeing the Answer posted by : DELL-Ravi CHi checked in BIOS screen, and checked in section Battery informationfirst both battery and charger was unknown
theni change the battery and now suffering from same problemnow it is showing the AC Adapter is Unknown
My Adapter is Original One then why it is showing adapter is unknownDid i have to change the Adapter
Thank you for writing to Dell Community Forum.
Can you check these adapter and battery on another system?
It could be an issue with either the motherboard or adapter itself.
Please click my DELL-username and send me a Private Message with the Dell Service Tag number and your email address.
Note: please don't mention the service tag or email id on the public forum as it contains your personal information
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