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Inspiron 3721 17R battery plugged in not charging

I have an inspiron 3721 17R , bought it from a friend. It runs windows 7.  It has new dell adapter and an used dell battery (with dell name on it)

The BIOS shows 90W for the adapter so it seems recognized.  However,

   a/ When boot, the screen says battery not recognized, and will not be charged. I have to press F1 to continue

b/ after logon to windows, the battery icon says plugged in not charging.

Please advise