I bought my first NAS nine years ago. I built my first computer that was dedicated to network file sharing 8 years ago, and I have been running UnRAID for probably 5 years now. Until Windows 10 file sharing has been relatively straightforward, since Windows 10 however it has been a painful experience.
My network had been running smooth for about a year, I thought I had all the bugs worked out, then I went to site for a week and when I returned my laptop couldn't reach any SMB file shares on my Unraid servers; that was almost two weeks ago. I hadn't dedicated a lot of time to fixing it, but it was much harder than I was thinking it would be. It wasn't until I couldn't even get a NFS share to mount on Windows 10 Pro that I thought that it was more than just a SMB issue.
Well at some point when I was away my computer must have updated and reverted a setting to a new default. I only found this out when I tried to mount the NFS share with:
net use z: \\server\mnt\share
This gave me an error stating that my organization doesn't allow unauthorized guest access. Well that was news to me.
Windows Error Code 1272
You can't access this shared folder because your organization's security policies block unauthenticated guest access. These policies help protect your PC from unsafe or malicious devices on the network.
This turns out to be a easy fix. go to the start menu and type gpedit.msc
Now navigate to Lanman Workstation (I have no idea what that means) and click Enable insecure guest logons.
Double click, enable and hit apply.
Then you're done.
Why did this happen?
I have no idea when this changed, but here are my current OS specs. I'm on version 1903.
So if you update and start to get strange errors connecting to share on your network whether it is with Unraid or any other NAS server, start with the normal fixes, but you may have to resort to this edit eventually.