Dell Laptop Battery Not Being Detected

I was given a 7-year old Dell Inspiron 6000 laptop to do a clean reinstall of Windows XP.

The battery in it is Dell-branded and appears to be the same one that came in it.

The charger works fine and kept the laptop powered during the entire setup/install/update process.

After I was done, I discovered in the power options and in the taskbar that the battery isn't being detected.

I examined the battery and the contacts and didn't see any damage or corrosion.

I wanted to update the BIOS, but I couldn't because of the "no battery detected" issue.

I realize a 7-year old battery likely no longer holds a charge, but why isn't it being detected?

I've never run into this issue before, so I'm stumped. :confused:

Anyone have any ideas?

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