Just a quick tip if you’re running into issues with SMB shares in macOS High Sierra. I was running into issues with my HP All-in-One Printer/Scanner and saving files to a network share on macOS. Apparently HP does not have SMB up-to-date in their firmware, so if you have strict signing or SMB protocol v3 setup, you need to downgrade it.
You can do that with the following set of shell commands:
sudo scutil --prefs com.apple.smb.server.plist get / d.add ProtocolVersionMap # 2 d.add ProtocolVersionMap # 1 set / commit apply quit
You may need to disable and re-enable the File Sharing service in macOS Preferences to get the changes to take effect.
Hope that helps!