I got the same issue with my portable SMB server. I kinda tried to find out the reason: it seems that HereSphere can’t read the “root” of the smb sever.
To be able to connect to my server I had to set the “SMB Path” on HereSphere UI to point out a specific path of my SMB.
To be short: HereSphere can’t read “/” of your SMB, you must set specific paths like: “/Movies/”, “/Anime/” if you have your SMB serve organized like me with subfolders.
And like you said, I can confirm that both SkyBoxVr and Pigasus are not affected by this issue, they can connect to my smb without specifing a path.