how do you import audio assets?

Every time I try to import an audio asset, I get the error 'file is not valid'

I even tried to save files in Ogg Vorbits and then bring them in, and when I check the Unity manual, it doesn't say any special orders for audio assets.

Determine whether Unity is acting up, or whether it's specific to the sound you're trying to import.

Try importing an MP3 file of a song. Download a free sound effect off the Internet in WAV format and try importing that. Do those fail, as well?

Unity will automatically detect files as they are added to your Project folder’s Assets folder. When you put any asset into your Assets folder, you will see the asset appear in your Project View.