Windows 10 - Cannot connect to SMB shares

Within my home network, the network drives [SMB shares] set up on a Surface 4 Pro [Windows 10 Home v2004, b19041.985], connected via ethernet, suddenly stopped working, and since the same are readily available on another Windows 10 machine, it doesn't seem to be an issue with the servers [Ubuntu server and QNAP NAS].

• The server is visible from the Surface 4 Pro, as pinging the server works, both using its hostname [servername] and IP address [192.168.1.3], with roundtrip times of <1ms and no lost packets, however:
  • net use X: \\servername\sharename returns error 59
  • net use X: \\192.168.1.3\sharename returns error 67
    
    
• I have, to no avail:
  • enabled File and Printer Sharing, Network Discovery and File Sharing
  • restarted several times
  • tried disabling Windows Defender firewall (nothing changed)

Any suggestions?

Solution 1:

I solved it by trying a simple net use without any parameters to see what I would get and received error 1222, leading me to investigate whether the work station service [lanmansworkstation] was running and it was not; I started it, but it returned a dependency could not be found.

In Registry Editor:

1. HKLM\SYSTEM\CurrentControlSet\Services\lanmanworkstation
   

   I changed the value of REG_MULTI_SZ: DependOnService from mrxsmb10 to:
   ^{(as far as I can see, mrxsmb10 is related to SMB 1.0, which I am not using)}

   bowser
   mrxsmb20
   nsi
   

   ^{Note: bowser must be spelled this way}
   
   

2. HKLM\SYSTEM\CurrentControlSet\Services\mrxsmb20
   

   I changed the value of DWORD: Start to 2 [Start Automatically]
   
   

3. HKLM\SYSTEM\CurrentControlSet\Services\mrxsmb
   

   Service mrxsmb20 is dependent on service mrxsmb, so I also changed the value of DWORD: Start to 2
   
   
4. I rebooted and the workstation service was still not running, so I went into services.msc and started it manually; et voilá, network shares work again