You don't say what operating system you're using, but you must have Quicktime installed on your computer in order to work with that file type in Premiere Elements 14.
But you also don't say where your video is coming from. Note that video and music from iTunes is blocked from usage in video editing projects by copy protection that Apple builds into the file. The result is usually a generic error.
Is this a video or audio file from iTunes?
The operation system for my PC is Window 7. The file is a video recording of a school performance (Lip Sync) recorded by our music teacher. I believe his computer is Apple instead of a PC, like teachers in many school do. I'll install Quick Time to my PC and report back.
By the way, do you think converting the .m4v file to .mp4 can solve the problem? If so, any suggestions? There are many free converters out there.
iTunes should be able to convert an m4v to an MP3. However, that will not resolve the issue if you are getting a generic error message. Converting the file doesn't remove iTunes' copy protection.
Other music sites, including Amazon.com, do not include such strict copy protection on their music files.
Following is a detailed description of how we end up with the .m4v file.
(1) We exported the footage from the camera to FCPX (Apple's Final Cut Pro X software).
(2) We did a rough edit and then shared the timeline from FCPX and created a .mov file.
(3) We brought that .mov file into Compressor and created a .m4v file.
Do you think I should try to export the footage directly from the camera or try to work with the .mov file?
Depends on what model of camcorder you're shooting it with.
If it's shooting a professional format of video, Premiere Elements may not able to read it.
If it's shooting a format like AVCHD or X-AVC, you should import the video directly from the camcorder to Premiere Elements.