You may receive an error during system startup stating "Unknown or Incorrect AC Adapter Detected."
Depending on the system, portable systems use either a 65W (Watt), 90W, 120W, 130W, 240W, or a 330W AC Adapter. Please make sure you are using the correct adapter for your system.
Please refer to the AC Adapters for use with your Dell system section of your manual to check on the proper adapter model approved for your system.
You can try to determine what is causing this error message, using the troubleshooting steps below.
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Note: XPS laptops purchased after April 2022, have AC Adapter LEDs that turn off after the AC adapter is connected to AC power or connected to the computer. This feature was added to reduce light pollution in low light environments. When connected to the wall outlet, the LED will illuminate for 10 seconds then turn off. When the USB Type-C connecter is plugged into the computer, the Adapter LED will flash six times in twelve seconds then turn off. This is normal behavior for XPS Laptop AC adapters for computers made after April 2022.
If the system is connected to a Docking Station, remove it from the Dock and test again with the correct AC Adapter for the system or try with a known good working AC Adapter.
If the message does not appear again, troubleshoot the adapter which is connected to the Docking Station, see the Docking Station section below.
- When the AC Adapter is connected to the mains supply, does the LED illuminate?
- The LED may be on the adapter brick or round the connector which plugs into the system.


(Figure 1.0 AC Adapter Green LED)
- If the LED does not illuminate:
- Check the mains socket for power and try another socket.
- Remove the Power Cable from the adapter brick, if applicable, and reseat it firmly.
- Remove the Power Cable from the system port and reseat it firmly.
- Check the adapter ports and cable for any damage. Replace the cable or adapter as necessary.
- Replace with a verified working adapter and test again.
- If the LED illuminates:
- Check the Adapter ports and cable for any damage. Replace the cable or adapter as necessary.
- Check the Adapter port on the system for any damage. If there is damage to the system port, please contact Dell Technical Support for assistance.
- Update the BIOS:
- Make sure the BIOS is up to date as there may be additional functionality within the BIOS for Adapter recognition.
Note: How to update the
BIOS.
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(Figure 2.0)
The D Series Docking station has an internal power supply and uses a Power cord only.

(Figure 3.0)
The D Series Port replicator uses a 90W AC Adapter.

(Figure 4.0)
The E Series Docking stations and port replicators use 130 W or 210 W AC adapter.

Warning: Make sure the AC Adapter that is supplied with the Docking station is not connected directly to the system.
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