Notes about the M4U file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The M4U file type is primarily associated with 'Ogg Media'. While non-standard, some use this file type for Ogg Media redirection. Use a text editor to create an .M4U file that contains a single line: the full URL to the .OGM file (e.g., MYVIDEO.M4U contains http://mysite.com/myvideo.ogm as its only entry). Use ASCII mode to upload the .M4U file and binary mode to upload the .OGM file. Be certain the server has application/ogg as the MIME type for the .OGM file extension and video/x-mpegurl for the .M4U file extension. You can then link to the .M4U file with the following HTML code: <a href="myvideo.m4u" type="video/x-mpegurl">Play My Video</a>
Detailed information for file extension M4U:
Primary association: Ogg Media
Mime type: video/x-mpegurl
To change file associations press Windows Key
and then Apps and Features
> Default apps
> Choose default apps by file type
Invalid file associations could be the result of underlying issues within your Windows PC.