Please Help - M17xR4 Adapter Not Recognized

When I boot up my laptop, I get a message that reads something along the lines of not being able to recognize my adapter. Once I get into Windows, it shows the adapter is plugged in, but not charging. I ordered and just received a new charger and battery today, but the problem persists.

In the BIOS, the adapter shows up as [UNKNOWN]. When running the ePSA diagnostic, it displayed my adapter as a 255w adapter, with charging: idle. The diagnostic passed with no errors. I have removed the battery, adapter, and done a minute long power drain, and that did not help. Additionally, I updated the BIOS from A05 to A12. None of these remedies have proven to be successful.

Does anybody have an idea of where to go from here? As I am out of warranty, Dell Support has been less than helpful; they even gave me an email address to "Alienware Support" that doesn't exist. Thanks in advance.