Encoded files are one line URL

[taco_bill1]

Hi -
I am trying to update the codec on old video as the later MAC OS does not support this encoding.

I first used VLC GUI to re-encode one item from current video to H.264 + MP3 (MP4). This worked great. I then scripted a command line to the same VLC and converted about 40 files correctly.

HOWEVER, certain files FAILED to take the new encoding (either with the VLC GUI or command line) and instead appear as a one line URL.
2,116,603 Jan 16 2014 VID_00000058.mp4
1214 Aug 29 19:40 VID_00000058_transcoded.m4v

cat VID_00000058_transcoded.m4v
ftypisommp41avc1moovlmvhdá2bá2b_%@ÿÿÿVåsttsstscstszstcotrak\tkhdá2bá2b@Ð$edtselst{mdia mdhdá2bá2bB@Ç-hdlrvideVideoHandler&minfvmhd$dinfdref
url æstblstsdavc1ÐHHÿÿ4avcCd ÿágd ¬Ù@P»iÐñ`hëì²,ýøøsttsstscstszstcoPudta$©reqQuickTime 6.0 or greater$©encvlc 3.0.18 stream outpuwidmdat^[[?64;1;2;6;9;15;16;17;18;21;22;28c64;1;2;6;9;15;16;17;18;21;22;28c

So basically a 2meg file goes to 1k and just has a URL. My MAC OS (Monterey has Quicktime version 10.5, so this is greater than 6.0.

This happens when I encode with the GUI or command line. The same GUI or command line arguments that worked on the other 40 files. I have 30 different files that have this same issue.

Any ideas?
Thanks!