Cannot connect to secure SMB3

[Taomyn]

Needs to support secure SMB3 as none of my shares are accessible now, and I know Linux can support this as my Kodi box is happily connected to the same shares.

https://docs.microsoft.com/en-us/windows-server/storage/file-server/smb-security#smb-encryption

[pascallj]

SMB3 is supported. I am running a SMB3_11 only server (Samba 4.9.5) with encryption set to required and it's working beautifully.

[Taomyn]

I did some more digging and discovered another test I was performing on my domain, disabling NTLM, was also applied to this server when it shouldn't have been. When I re-enabled NTLM and waited, it started to work. I also found it was the same for Kodi so must have been a cached connection at the time.

Looks like the issue is that the Samba client doesn't support non-NTLM authenticated connections, something it really needs to do as having NTLM enabled on modern Windows servers is already logging warnings that it should be disabled for security. So not long before it's off by default.