+1
There are definitely still some bugs in Volumio when it comes to mounting remote shared drives. I remember tearing my hair out over this when I was trying to get it to point at my NAS box. It was another good reason for moving to MinimServer as this circumvents all of that hassle.
I'm not sure if this will help, but as I remember it, Volumio has trouble with mounting guest accounts, so you're better off with a proper login and password, but even then, there is a bug in the underlying Linux kernel. Something worth trying is to click the Advanced options at the bottom of the screen and add sec=ntlm to the end of what is already on that line - start with a comma to delimit it from any options that precede it. This worksaround a cifs/samba bug in the Linux client and I remember that helped me when I was using Volumio to perform remote share mounting.
There is a discussion here that goes into more depth:
https://volumio.org/forum/problems-m...ares-t158.html