How much is the upper limit of video capacity when we use Video Editing? I tried to edit about a 4.2GB-mp4-video, but Blender said "File A could not be loaded." The video length was almost 3 hours.
On the other hand, when I tried to load the only first 1 minute of the beginning,
Blender succeeded to load it and to display the sequences.

I think Blender may have the upper limit of movie capacity.
Can anyone tell me how much capacity Blender accepts?
Blender has the frame number limit.

Working Limits : Time


  "The maximum number of frames for each scene is currently 1,048,574,
  and allows for continuous shots for durations of:
  
  24 fps:   12 hours, 8 seconds.
  
  25 fps:   11 hours, 39 seconds.
  
  30 fps:   9 hours, 42 seconds.
  
  60 fps:   4 hours, 51 seconds."


But in your case this could be insufficient RAM as well.