I have a large MP4 video. When I try to add it as media, I get "Warning: An error occurred while opening one or more files. The file could not be opened. Make sure the file exists and that you have access to the file/folder.
@TIm-Kestermont We await Media info as per j-v's link. Whilst mp4 is a common file type it is only a container and we need to know what's inside it in order to be able to help.
I believe the issue is file size. Putting together 1.5 hours of a documentary. The file is too large. Other smaller MP4’s work. I have plenty of space.