File sharing,networking and SMB

Configure the Windows 11 host for authenticated file sharing over SMB2/3; do not enable SMB1 or weaken SMB signing unless a specific error proves that a legacy device requires a compatibility change.

Configure the Windows 11 PC hosting the share

1. Set the network profile to Private
   • Open Settings → Network & internet.
   • Select the active Wi-Fi or Ethernet connection.
   • Set Network profile type to Private.
2. Enable sharing
   • Go to Settings → Network & internet → Advanced network settings → Advanced sharing settings.
   • Under Private networks, turn on:
     • Network discovery
     • File and printer sharing
3. Share the folder
   • In File Explorer, right-click the folder.
   • Select Show more options → Give access to → Specific people.
   • Select the Windows user who should connect. Use Everyone only when broad LAN access is intentional.
   • Choose Read or Read/Write, then select Share. Windows documents this procedure for Windows 11 network shares.^1^
4. Use an account with a password
   • From the other PC, connect with the username and password of an account authorized on the hosting PC.
   • Share permissions and the folder’s Properties → Security permissions must both allow that account. If either denies access, the effective result is denied.^2^
5. Test the share locally
   • On the host, enter \\localhost in File Explorer. This displays folders shared from that PC.^1^
   • Then test \\localhost\ShareName.
6. Connect from the other computer
   • In File Explorer’s address bar, enter:

          \\HostComputerName\ShareName
     

   • Prefer the computer name rather than its IP address.
   • To retain it as a drive, open File Explorer → This PC → More → Map network drive, enter the same UNC path, and select Reconnect at sign-in.^1^

If the PC or share is not discovered

Direct UNC access and visibility under File Explorer’s Network page are separate. If the UNC path works, SMB itself is working even if the computer does not appear under Network.

On the hosting PC:

1. Press Windows+R, enter services.msc, and select OK.
2. Set these services to Automatic and start them:
   • Function Discovery Provider Host
   • Function Discovery Resource Publication
   • SSDP Discovery
   • UPnP Device Host

These services and the advanced-sharing settings are Microsoft’s documented discovery configuration.^1^

If security software or Windows Firewall is blocking the connection, allow File and Printer Sharing on the Private network. Do not leave the firewall disabled; a brief disable-and-test is only a diagnostic and should be reversed immediately.^3^

Identify an actual SMB security block

Because the previous error is no longer available, it is not possible to determine whether SMB protocol policy caused that failure. If it happens again, run these commands on the computer opening the share:

net use
Get-SmbConnection
Get-SmbClientConfiguration |
    Format-List RequireSecuritySignature,EnableInsecureGuestLogons

Also inspect:

Event Viewer → Applications and Services Logs → Microsoft → Windows → SMBClient → Connectivity and Security

The error text or event determines the correct branch:^2^

• “Unauthenticated guest access” or Event ID 31017: use valid credentials for an account on the host. Do not enable insecure guest logons as the normal fix.
• Access denied for only one user: correct both the folder’s Sharing and Security permissions.
• Windows 11 24H2 signing error with a third-party NAS/server: enable SMB signing on that device. This does not normally apply when another Windows 11 PC hosts the share.
• Name works but IP does not, or vice versa: use the hosting computer’s name and investigate name resolution or authentication rather than changing SMB versions.

Do not enable SMB1 for this Windows 11-to-Windows 11 share

Windows 11 does not install SMB1 by default, and Microsoft strongly discourages using it because of significant security vulnerabilities. Windows 11 systems can negotiate SMB2/3 without it.^4^

Likewise, do not disable SMB signing merely to make a connection work. Windows 11 24H2 Pro, Enterprise, and Education require inbound and outbound signing, while Windows 11 24H2 Home does not require it by default.^5^

References

1. [Windows 11](https://support.microsoft.com/windows/experience/connectivity-networking/file-sharing-over-a-network-in-windows)
2. Access Denied when you access an SMB file share in Windows
3. File Share Not Working - - Microsoft Q&A
4. Detect, enable, and disable SMBv1, SMBv2, and SMBv3 in Windows
5. Control SMB signing behavior