I ran into this recently after it had been working ever since I built & installed this Windows 10 computer, as well as on every other machine on the network. The particular issue was that not a single Linux machine could mount shared Windows 10 drives, even though they had all previously been able to. After seeing Sean Gray's response above, I checked, and sure enough, the last Microsoft update had switched my network to Public and disabled all my firewall settings. Lovely. I reset the adapter and made my private network private, as it should have been, fixed the firewall, and now everything works correctly.
The next time you get a 'mount error(2): No such file or directory', or the referenced NT_STATUS_IO_TIMEOUT error if you're using smbclient to troubleshoot, then check your Windows firewall AND your Windows network adapter settings. That "public/private" network setting just might be what's biting you.