Windows 11 25H2 File Sharing Not Working? 10 Fixes for 2026

If you’re dealing with Windows 11 file sharing not working after installing the 25H2 update, you’re far from alone. Thousands of users are reporting broken SMB connections, invisible network devices, and stubborn “access denied” prompts when trying to open shared folders. Microsoft’s 25H2 release tightened several security defaults, and while that’s great for protection, it has effectively disabled features many home and small-office networks rely on. The good news? Every one of these issues has a working solution. In this guide, we’ll walk through ten proven fixes to restore reliable LAN sharing across your Windows 11 devices in 2026.

Why Windows 11 25H2 Broke Your File Sharing Setup

The Windows 11 25H2 network sharing changes weren’t accidental. Microsoft removed SMB1 support entirely from Home and Pro editions, enforced SMB signing by default, and disabled guest fallback authentication. If your NAS, printer, or older PC relied on any of these, sharing will simply stop working after the update.

On top of that, the update resets several network policies. Network discovery often switches itself off, private networks get reclassified as public, and Windows Defender Firewall reintroduces rules that block inbound SMB traffic. The result is a perfect storm of small changes that add up to complete sharing failure.

Before diving into fixes, identify what changed. Ask yourself: did sharing work before 25H2? Are you sharing between two Windows 11 PCs, or does a NAS/Linux box sit in the middle? The answers determine which fix applies.

Quick Diagnostic Checklist

• Both devices are on the same subnet and connected to the same router
• Network profile is set to Private, not Public
• File and Printer Sharing is enabled in Windows Defender Firewall
• You know the exact username and password of an account on the sharing PC
• The shared folder has both share-level and NTFS permissions granted

Fix 1: Re-enable Network Discovery and Sharing

The most common cause of windows 11 network discovery off issues is a silent reset during the 25H2 upgrade. Turning it back on takes about a minute.

1. Open Settings and go to Network & Internet > Advanced network settings.
2. Click Advanced sharing settings.
3. Under Private networks, toggle on Network discovery and File and printer sharing.
4. Expand All Networks and turn off password-protected sharing only if you specifically need guest access (not recommended for most users).
5. Click Save changes and restart both PCs.

Pro tip: If the toggles keep reverting to off, it usually means the Function Discovery services are disabled. Press Win+R, type services.msc, and set both Function Discovery Provider Host and Function Discovery Resource Publication to Automatic (Delayed Start).

Fix 2: Switch Your Network Profile to Private

Windows blocks nearly all inbound sharing traffic when a network is marked Public. After the 25H2 update, many home networks silently get reclassified as public, which is often the real reason SMB stops responding.

1. Open Settings > Network & Internet.
2. Click your active connection (Wi-Fi or Ethernet).
3. Under Network profile type, select Private network.
4. Repeat on every Windows 11 PC involved in the share.

If the option is greyed out, it usually indicates a corporate policy or a captive portal state. Reconnect to the network and try again once the connection stabilises.

Fix 3: Fix SMB Share Not Working on Windows 11

An smb share not working windows 11 error after 25H2 almost always traces back to protocol version conflicts. Modern Windows only speaks SMB 2.0 and higher, but many NAS units and older devices still rely on SMB1. You have two paths: upgrade the other device or, if impossible, temporarily re-enable legacy SMB support.

Enable SMB Client Support for Legacy Devices

1. Open Windows Features by typing “Turn Windows features on or off” in the Start menu.
2. Scroll to SMB 1.0/CIFS File Sharing Support.
3. Expand it and tick SMB 1.0/CIFS Client only — leave the server component off.
4. Click OK, then restart your PC when prompted.

Warning: SMB1 is insecure and vulnerable to WannaCry-style ransomware. Enable it only as a temporary bridge while you upgrade your NAS firmware or replace an ageing device.

Force SMB2 Signing Compatibility

If your NAS supports SMB2 but connections still fail, run this in an elevated PowerShell:

1. Set-SmbClientConfiguration -RequireSecuritySignature $false
2. Set-SmbClientConfiguration -EnableInsecureGuestLogons $true

Both commands relax the strict 25H2 defaults. Reverse them once your NAS firmware is up to date. For a broader look at how Microsoft is redesigning authentication across the OS, our walkthrough on setting up passkeys on Windows 11 25H2 without a Microsoft account covers the same security trend from a different angle.

Fix 4: Resolve Shared Folder Access Denied on Windows 11

A shared folder access denied windows 11 message almost always means one of two things: your user account lacks NTFS permission, or the credentials being sent don’t match anything on the target PC. Fixing this requires checking both layers.

1. On the PC hosting the folder, right-click it and choose Properties.
2. Under the Sharing tab, click Advanced Sharing, then Permissions.
3. Add the specific user account (not “Everyone”) and grant at least Read permission.
4. Switch to the Security tab and confirm the same user has NTFS Read & Execute rights.
5. Click Apply and OK on all dialogs.

When you connect from the other PC, use the format HOSTNAME\username (or MicrosoftAccount\email@address if the host uses a Microsoft account). Tick Remember my credentials to avoid re-prompts.

Clear Cached Credentials That Went Stale

Windows Credential Manager often caches broken logins from before the update. Open Control Panel > Credential Manager > Windows Credentials, expand any entries beginning with the target PC’s name or IP, and click Remove. Reconnect fresh and enter the correct credentials once.

Fix 5: Repair Firewall and Service Configuration

The Windows Defender Firewall in 25H2 reintroduces a bug where the File and Printer Sharing rule group appears enabled but is silently blocked. Re-adding the rules manually solves it.

1. Open Windows Security > Firewall & network protection.
2. Click Allow an app through firewall > Change settings.
3. Scroll to File and Printer Sharing and tick both Private and Public boxes (yes, both — you can untick Public after testing).
4. Also enable Network Discovery in the same list.
5. Click OK and test the share.

Next, verify the three critical services are running: Server (LanmanServer), Workstation (LanmanWorkstation), and TCP/IP NetBIOS Helper. Any of these being stopped will kill sharing instantly. Set all three to Automatic startup.

Fix 6: Use IP Address Instead of Hostname

NetBIOS name resolution frequently breaks after 25H2, especially in mixed networks with routers that don’t fully support mDNS. Instead of typing \\LIVING-ROOM-PC, try the IP address directly: \\192.168.1.42.

To find the target PC’s IP, open Command Prompt on it and run ipconfig. If IP-based access works but names don’t, the problem is DNS/NetBIOS — reserve a static IP in your router for that machine as a permanent workaround.

For deeper networking troubleshooting patterns that apply across platforms, the diagnostic mindset in our guide to fixing Apple Intelligence slow response times is surprisingly similar — isolate the failing layer before touching anything else.

Fix 7: Reset the Entire Network Stack

When nothing else works to fix windows 11 lan sharing, a full network reset clears every stale adapter, cached DNS entry, and orphaned Winsock catalog entry from the 25H2 upgrade. It’s aggressive but nearly always effective.

1. Open Settings > Network & Internet > Advanced network settings.
2. Scroll to Network reset and click it.
3. Confirm with Reset now — the PC will restart in five minutes.
4. After reboot, reconnect to Wi-Fi, set the profile to Private, and re-enable network discovery.

Warning: You’ll need to re-enter your Wi-Fi password and reconfigure any VPN clients. Save credentials beforehand.

Fix 8: Check Router-Level Client Isolation

Many mesh routers and ISP-supplied gateways ship with “AP Isolation” or “Client Isolation” enabled by default in 2026. This blocks devices on the same Wi-Fi from talking to each other — meaning file sharing will never work no matter what Windows settings you change.

Log into your router’s admin page (usually 192.168.1.1) and search settings for terms like isolation, AP isolation, or client separation. Disable it on the 2.4 GHz and 5 GHz bands. On mesh systems, also check the guest network settings, which sometimes bleed rules into the main SSID.

Fix 9: Verify Account Type Compatibility

Microsoft accounts, local accounts, and Azure AD accounts all authenticate differently over SMB. If the host is on a Microsoft account and the client is on a local account, you’ll need to use the full email address as the username.

Consider creating a dedicated local account on the host PC purely for sharing: give it a strong password, add it to the folder’s permission list, and use those credentials from every client. This is the most reliable long-term setup for mixed home networks and avoids the quirks that come with cloud-linked identities.

Fix 10: Roll Back or Repair the 25H2 Update

If sharing worked flawlessly on 24H2 and completely broke after 25H2, and none of the fixes above stick, a targeted rollback is legitimate.

1. Go to Settings > Windows Update > Update history.
2. Click Uninstall updates.
3. Find the 25H2 feature update entry and click Uninstall.
4. Once reverted, pause updates for 35 days to give Microsoft time to ship a patch.

Alternatively, run an in-place repair install using the Windows 11 Installation Assistant. Choose “Keep personal files and apps” — this rebuilds system files without touching your data and often resolves the deepest sharing corruption.

Frequently Asked Questions

Why can’t I access shared folders on Windows 11 25H2?

The most common causes are the network profile being set to Public, SMB1 having been removed, guest login being blocked by default, or Credential Manager holding stale logins. Work through fixes 1, 2, and 4 in order — one of them resolves the issue in roughly 80% of cases.

How do I enable SMB1 on Windows 11?

Open “Turn Windows features on or off,” expand SMB 1.0/CIFS File Sharing Support, and tick the Client component. Restart when prompted. Only do this if a NAS or legacy device requires it, and disable SMB1 again as soon as you upgrade the other device — it remains one of the most exploited protocols in home networks.

Why is network discovery turned off automatically?

Windows disables discovery automatically whenever it detects a Public network profile, or when the Function Discovery services are stopped. The 25H2 upgrade resets both. Set your network to Private and ensure Function Discovery Provider Host and Function Discovery Resource Publication are set to Automatic (Delayed Start).

How do I fix ‘access denied’ on shared folders?

Access denied means authentication succeeded but permissions failed. Check both Share permissions (Sharing tab > Advanced Sharing > Permissions) and NTFS permissions (Security tab) — the effective permission is whichever is more restrictive. Add the specific user account to both lists and grant at least Read access.

Does Windows 11 25H2 block file sharing by default?

It doesn’t block sharing outright, but it enforces stricter defaults: SMB signing is required, guest logins are refused, SMB1 is gone, and network profiles default to Public on unknown networks. For most home users this feels like sharing is “blocked,” but it can be re-enabled safely with the steps in this guide.

Wrapping Up: Restoring Reliable File Sharing in 2026

Fixing windows 11 file sharing not working in 25H2 is rarely about one single setting — it’s about aligning the network profile, firewall rules, SMB protocol version, and user credentials at the same time. Work through the ten fixes methodically, restart between major changes, and always test with the IP address before blaming DNS. Nine times out of ten, the culprit is either a Public network profile or a stale cached credential from before the update.

Want to keep locking down and modernising your Windows 11 setup? Take a look at our guide on setting up passkeys as the default login on Windows 11 in 2026 to strengthen authentication across your devices, or explore our 2026 review of Bitwarden as a cross-platform password manager if you’re consolidating credentials across your home network. And for more Windows, macOS, and mobile troubleshooting, browse the latest from the Hawkdive team.