If you change the VarDir setting, create a file content and try to access it directly you will get an unhanded exception (see attached stack trace) instead a 404.
Argument '$id' is invalid: Prefix images not found in original/video/4bdd7ff
b1324dc94c291c066e3fc797c.mov
*500 Internal Server Error ­ InvalidArgumentException*

If you use the default VarDir, you will get a 404 page.

Steps to reproduce

• Change the VarDir settings in you legacy "override/site.ini.append.php" and your "config/ezpublish.yml" to "var/storage".

  VarDir=var/storage

• Go to your backend, create a file content with a video file. Let's say, "my_test.mov".
• Confirm the file was created in the correct VarDir:
  "./ezpublish_legacy/var/storage/storage/original/application/9f88d3cbec3bbfa4f5757e46d7bd1894.mkv"
• Try to access it with the API or just open the link in your browser:
  http://my-site.comt/var/storage/storage/original/application/9f88d3cbec3bbfa4f5757e46d7bd1894.mkv
• Confirm you will get the exception.

^{Note: If you change the VarDir to the default "VarDir=var/ezdemo_site" value, and try to open the URL, you will get a handled 404:
http://my-site.comt/var/storage/storage/original/application/9f88d3cbec3bbfa4f5757e46d7bd1894.mkv}