VLC Error – Unable to open the MRL

I love VLC media player, but I have tried to get it to work on Raspbian (Pi) and Debian (PC) with little success. I always got the following error:

VLC is unable to open the MRL 'filename_redacted.mp4'

When you search the big G for info it throws back a lot of posts suggesting it’s an issue with your firewall. This may well be the case, but for me it was a simple authentication issue.

I’m using VLC 2.2.4 Weatherwax to access a file shared from my NAS using Samba. To solve the problem I went to:

VLC > Tools > Preferences > Show Settings (All) > Input/Codecs > Access Modules > SMB

Whereupon I entered credentials for the NAS. It now works.