Dell Latitude E5520 plugged in, not charging

I recently purchased a used Dell Latitude E5520 laptop that didn't work.  I found that the hard drive was bad, and so replaced it with a new one.  I was able to determine that it had Windows 10 on board.  The license was for Windows 7 Pro, so I installed Windows 7 Pro 64 bit, and then updated to Windows 10 pro 64 bit, and, after all was said & done, now have Windows 10 Pro 64b Creators Upgrade on board.  

However, it now shows "Plugged In, not charging".  The battery was at 0%.  So I searched all of the posts on this issue, and followed all of the steps (removing the battery, deleting the battery software, reinstalling the battery, buying a new battery, updated the Bios & Chipset, etc0).   So far no change.   

The charger I have is a Dell 90W AC Adaptor model # LA90PS0-00.  With the charger plugged in, and the battery removed, the laptop powers up and runs fine.  When I first got the laptop, the battery (Dell T54FJ) lasted for well over an hour from a partial charge, however couldn't get it to charge.  The new battery currently has 60% charge, but still not charging.  When I first plug the power supply in, the "Charger plugged in" light (the small lightning bolt on the left of the keyboard) lights up, but goes out after a second or two.  

I am at a loss as to where to go from here.  I have a multimeter, and can test the output of the power supply, however I cant find any specs that tell me what the readings should be.   I don't want to replace it until I am sure this one is bad or not.

Any ideas?