One W10 Pro client unable to access SMB

TrueNAS General
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In my network, only one client fails to access SMB. It can login in the AD, leave the AD and join the AD without issues, which is what makes me think the issue is with SMB/TrueNAS.

I’ve already set the logs to “Debug” in “SMB” in the “Services” tab of the TrueNAS GUI, but attempts at mounting a network drive from the W10 machine (e.g.), does not produce a line output in /var/log/samba4/auth_audit.log

On the W10 machine, the error tells me the password is wrong, but I’m positive it’s not. I can easily test it on other machine as this is the only one computer failing.

Finally, I’ve found this topic on the old forums (can’t include links here, but the topics subject is : " SMB Problem on WIN 10 Client (FN11-RC)"),
which seemed extremely promising, but adding LmCompatibilityLevel in “HKLM\SYSTEM\CurrentControlSet\Control\Lsa” and setting it to either 3 or 5 didn’t do anything, and, in secpol.msc on the problematic machine, the setting was already to use NTLMv2 and refuse anything else, like advised in this thread.

I am at a complete loss, and available to log anything, just let me know what I can try/provide to debug this.

Many thanks,
A

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That’s odd. Just for be sure, you are not forcing NTLMv1 on SMB share right?

In my little experience, credentials error like yours are always client related (and the fact other machine can connect should confirm that).

If you are using an hostname to connect, do you already check if It Is well resolved?

Have you try to mount using the command line?

net use X: \\server\share /user:user password
(If i well remember, maybe check sintax first)

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Try to determine “from where” the password is taken. I would think about it not so much in terms of right/wrong. Rather that the value is “unexpected”. The typical cause in this class of error scenarios is that a value is taken from a different place than what is expected.

You could create a new user (not use an existing one!) as a first check. Also, I would change the password for the user you tested with so far. Doing such things and comparing results, will often get you closer to understanding what is actually happening. The latter is key to solving the issue!

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I had this same problem 2 days ago after a security update from Microsoft. I had to roll back in order to fix it. It affected only one TrueNAS machine SMB shares. Blew my mind.

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Thank you for the answers.

After trying every suggestion you all gave, I ended up being noticed of an issue on another computer that… shared the same name in the AD.

Quite embarrassing.

After battling a bit, leaving and joining the AD, using brand new computer names… it’s solved, nothing to do with TrueNAS afaik.

Cheers and thanks for your time.

2 Likes
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Glad you solved it. I wish it was the same issue I had so I would know what the solution is for me. Eh, I will cross that path probably soon again.