In PE 14 I have an audio mp3 file which I have used several times in different projects without a problem. PE has now abruptly stopped even recognizing this file when I try to import it via Add Media followed by Files & Folders on the PC. It just doesn't show up in the list of files when I navigate to the relevant folder.
I have tried converting the file to a different format (WAV) but the problem remains the same. I then altered the default progam the file opens with from iTunes to PE14. In that case opening the file does cause it to be opened in PE14 as a brand new project. That is unsatisfactory because I want to import it into an existing project.
Even if the file were using a codec or some other compression system that Premiere Elements can't read, you'd still be able to see the file when you browsed to it from Add Media/Files and Folders. It's just an MP3 or a WAV file.
If you literally can not see the file when you browse to it from Premiere Elements, something is going on that's not related to the program.
Though you wouldn't see a media file if you were using File/Open, since it opens a browser that only sees project files. But you're sure you chose Add Media, so I don't know what is up.