Do you remember the news a few years ago about battery fires? Dell among other makers reacted by locking out third part batteries. If the battery is from Dell, call them and ask if they have a fix.
Bob
I replaced an old 6cell dell vostro battery with a new 8 cell replacement, and the laptop ran fine with it, the AC is not charging it. The LED battery indicator only briefly came on, at start up, and then went out.

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