Thanks, but I tried that. Didn't solve my problem.

Here's what I know: 1. Mac Mini (on El Capitan) has a remarkably resilient smb connection to the nas on port 139. 2. I've tried both "smb ports = 445" and "smb ports = 139 445" in my smb.conf; mini connects regardless but Air (Sierra) doesn't ever; could never see a connection on 445 in nas netstat. 3. my nas is on samba 3.0.23c. 4. I've tried upgrading nas to samba 3.6, but the package binary I'm trying to use is looking for older libiconv and libldap than I can find. 5. My nas is a MyBook World Edition from 2008, which probably means I should upgrad to synology or something.

I've spent four hours on this today, and I'm nowhere closer to solving this issue. Here's what I know: * Mac Mini (on El Capitan) has a remarkably resilient smb connection to the NAS on 139.

Thanks @uldo, that helped me find out that my Mac Mini is connecting over port 139. I'll try listening on 445 again.

My smb.conf didn't have an smb ports line. I tried adding "smb ports = 445" to it (w/o quotles) and restarted my server. Still not getting through. Thanks for the suggestion, though. It would make sense that there's a conflict between what the server is expecting and what my Mac is sending.