Mac mini can't connect to my corporate SMB server. Was working some days ago I'm at work, and my Mac mini has stopped being able to connect to the corporate SMB server shared folders.

If I try Finder > Connect to Server (using the URL stored there from previous successful connections), macOS Sierra complains with a more than useless "generic error".

In my Console logs I can't detect any error related with samba (where should I be looking into?)

There are clonic Mac mini machines on the same floor (my coworkers' ones) and they can connect to this server without any problem.

If I ping this machine from my command line, I can see it perfectly.

If I try this on the command line:

smbutil view smb://192.168.XXX.XXX/docs/


macOS Sierra yields this:

smbutil: server connection failed: No such file or directory


If I try that very exact command line onto a coworker machine, it just lists the shared resources hanging from that SMB server...

Any hint? Maybe it's something related to some service being disabled by mistake in my Mac mini?

I don't have access to my company Samba Server machine and configuration.

I've read and googled many pages around and I'm more than lost.

In case it might be useful, I use MacPorts. It might seem a random thing to add here, but maybe I'm not aware of some library I might have installed that might be known to be troublesome with the official OS X SAMBA client.
SUCCESS!!

After 2 months of (moderate) misery I've finally found the reason SMB didn't work with my Sierra Mac Mini.



TL;DR The reason was this installed kext:

com.intel.kext.intelhaxm (6.0.1) 8FF2C637-0A5E-367E-B007-5B08655B1E8A &lt;7 5 4 3 1>

You can check if you have it installed with the following command from an ordinary Terminal:


  kextstat | grep -iv apple


In case you have it (and in case you're also suffering SMB connectivity problems) you can uninstall it typing the following command, again, from an ordinary Terminal (no need to boot in Single-User mode):


  sudo /Library/Extensions/intelhaxm.kext/Contents/Resources/uninstall.sh


Follow the on-screen instructions, REBOOT, and you're done :) 

Doing that you'll lose hardware acceleration inside your Android emulators, but they will work in software-rendering mode. Not brilliant, but it's something. You can reinstall HAXM in case you really need Hardware Acceleration for Android emulators again (but be prepared to lose SMB connectivity again (?)).



Long answer:

If you use your Sierra Mac to develop Android stuff you'll probably have installed the typical random needed modules (Android SDK's, emulators, drivers, etc...)
The thing is, "Intel HAXM accelerator" is one of the typical drivers you install if you want proper hardware acceleration of your emulators for Android developing.
Well, apparently, and believe it or not, that driver is not compatible with using SMB under macOS Sierra, at least with my MAC.

Sierra SMB subsystem and HAXM are apparently unrelated pieces of software, but it seems they are somehow incompatible between them. In case you have SMB problems you'll have to decide which of the two you really need more:

SMB or proper fast emulators for Android development.

I chose SMB  :)



Thanks EVERYONE in this question, answering, commenting, etc... specially Brett who, after many weeks, put me after the correct lead.