Below is a list of actions that can be taken if your computer is not recognizing your headphones:

1. Check the audio jack of the headphones to see if the connection is secure.
2. Make sure that the audio drivers on the computer are up to date.
3. Check that your sound card is properly connected.
4. Restart your computer, check if the audio control settings have been changed.
5. Check that the audio output is set to the correct audio source.