If you reached "VC76 mp4" due to a video playback error, you may be misremembering professional video codecs like (Dirac Pro) or VC-3 (DNxHD), which can sometimes be wrapped in MP4 or MOV containers.
: Available for both macOS and Windows as VST, AU, and AAX plugins.
The search for "Download VC76 mp4" reveals a common point of confusion between a popular and general video file formats .