Unable to Import Video Files

I was working on a project a few months back, and am revisiting it now. Except all the .mp4 video files I had been using previously are no longer importing.

The files were moved to different folders, but when I try and locate them I get an error message saying "The importer reported a generic error." If I try importing them directly, I get a different error message saying "Unsupported format or damaged file." I get a similar error when importing to After Effects reading: "After Effects error: File "name" cannot be opened, it may be in an unsupported format. ( 86 :: 1 )".

However, the videos are all playable in VLC Media Player without issue.

I'm working with PremierePro 2025 on Windows 10; I've cleared the Media Cache, I've tried moving the files back to their original folders, I've tried redownloading fresh versions of the videos, and I've tried uninstalling and reinstalling Premiere, but nothing is working. I'm not sure what's causing this issue, so if anyone can share some potential causes/fixes I would really appreciate it!