Peer to Peer networking Broken

Question

Can someone settle me down & point me to a resolution? I am getting very frustrated by Microsoft breaking the P2P networking shares & Mapped drives. This is the second time in 6 weeks ! Connection being lost, getting error message that the password is incorrect when attempting to restore the mapped drive. I have tried the fixes that I have been able to find to no resolution for second Break in early Dec 2025. First Break on Oct 3, 2025, solution is basically listed below. Scenario 8 Dell OptiPlex 6 Core i5-9500, 32GB, NEW 1TB NVMe, SFF PC Computer Win11 Pro, Wi-Fi5 is used for networking. All computers with same hardware on all LOB program on what we will call server.

First Break, Cause: updated windows 11 KB5065426 Security Update network shares no longer connect:

First Fix I Used: Stop & Clear WU

Ran SFC

Ran DISM per https://windowsreport.com/0x80242016/

Copy and paste the following command to stop the Windows Update service and press Enter. You might have to do it a couple of times to ensure it is not running:

taskkill /f /fi "SERVICES eq wuauserv"

Type the following commands one after the other and press Enter after each command:

net stop cryptSvc

net stop bits

net stop appidsvc

net stop msiserver

net stop wuauserv

ren C:\Windows\SoftwareDistribution SoftwareDistribution.old

rmdir C:\Windows\SoftwareDistribution\DataStore

rmdir C:\Windows\SoftwareDistribution\Download

Ren C:\Windows\System32\catroot2 Catroot2.old

net start wuauserv

net start cryptSvc

net start appidsvc

net start bits

net start msiserver

sfc /scannow

dism /online /cleanup-image /scanhealth

dism /online /cleanup-image /checkhealth

dism /online /cleanup-image /restorehealth

"[SMBv1 protocol connectivity (known issue)] Fixed: An issue where you might not be able to connect to shared files and folders if you're using the Server Message Block (SMB) v1 protocol on NetBIOS over TCP/IP NetBIOS (NetBT). This can happen after installing update KB5065429."

Resolution disable SMBv1 in Windows Features & uninstall windows 11 KB5065426 Security Update

Second Network Break

Twist is very weird! One workstation and the server can run the LOB software. The One Workstation for some reason did not lose Mapped Drive connection & access! All setting are the same in all other workstations.

Re-did the First solution steps. No joy at all. I have even attempted to create new share from another computer but cannot access/ map it either.

I have done everything except remove Share from server computer and try to restore it that way but, my attempt to share/ Map from a different workstation failed so I do not see that as a complete solution.

Any help/ Responses will be appreciated.

Answer 1

It sounds like you're experiencing persistent issues with mapped drives and network shares in a peer-to-peer (P2P) environment, particularly after Windows updates. Here are some steps you can take to troubleshoot and potentially resolve the issue:

1. Check Network Settings: Ensure that all computers are on the same network and that network discovery is enabled. You can do this by going to Settings > Network & Internet > Status > Network and Sharing Center > Change advanced sharing settings.
2. Disable SMBv1: Since you mentioned issues related to SMBv1, ensure that it is disabled. You can do this by going to Control Panel > Programs > Turn Windows features on or off and unchecking SMB 1.0/CIFS File Sharing Support.
3. Adjust Autodisconnect Settings: The default timeout for network connections can lead to disconnections. You can increase the timeout period for the autodisconnect feature of the Server service. Open a command prompt and run:

      net config server /autodisconnect:30
   

   This sets the timeout to 30 minutes. You can adjust the number as needed, up to 65,535 minutes.
4. Registry Changes: If the above does not work, consider adjusting the registry settings for autodisconnect and KeepConn as follows:
   • Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters and set autodisconnect to a higher value or create it if it doesn't exist.
   • For client-side settings, navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanworkstation\parameters and set KeepConn to a higher value (in seconds).
5. Recreate Mapped Drives: If you're still having issues, try removing the mapped drives and recreating them. Ensure that you have the correct permissions and that the shared folders are accessible.
6. Check for Windows Updates: Sometimes, specific updates can cause issues with network connectivity. Ensure that your system is fully updated and check for any known issues with the updates you have installed.
7. Firewall and Antivirus Settings: Ensure that your firewall or antivirus software is not blocking the connections. Temporarily disable them to see if that resolves the issue.
8. Event Viewer: Check the Event Viewer for any error messages related to network connections or SMB. This can provide more insight into what might be going wrong.

If these steps do not resolve the issue, you may need to consider contacting Microsoft support for more specialized assistance.

---

References:

• Mapped drive connection to network share may be lost
• Mapped network drive may fail to reconnect in Windows 10, version 1809

Answer 2

Hi there,

What makes your case particularly tricky is the inconsistency: one workstation keeps the mapped drive alive while the rest drop it, which usually points to a credential cache / NTLM hardening mismatch introduced after the November–December 2025 updates, not just an SMBv1 deprecation issue.

There are a few targeted checks I would strongly recommend at this stage, especially since you’ve already gone through the full WU reset, DISM, and SFC cycles:

1. Verify NTLM Hardening Policies (these have changed silently with KB5065426 and later). On all workstations and the “server,” check: Local Security Policy > Local Policies > Security Options > “Network security: LAN Manager authentication level.” Set it temporarily to: Send NTLMv2 response only and ensure “Network security: Restrict NTLM: Outgoing NTLM traffic” is NOT set to “Deny all.” These policies have been reverting or tightening during the latest updates, and this alone can block mapped drive reconnection with “incorrect password.”
2. Clear all stored Windows Credentials that reference the server, then recreate the mapped drive using explicit credentials. The one workstation that still works likely has an older, valid NTLM token cached.
3. Check if SMB signing was auto-enabled by the patch. If the “server” does not support signing, but the clients suddenly require it, you’ll get silent failures or endless password prompts. Check: HKLM\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters Ensure RequireSecuritySignature = 0 (for testing).
4. Confirm that Function Discovery Provider Host (FDPHOST) and FDResPub are running. Recent updates have disabled these services on some OEM images, breaking peer discovery even when shares are correct.
5. Test with UNC path explicitly using IP, not hostname: \\192.168.x.x\sharename If this works but hostname fails, then LLMNR/NetBIOS name resolution was impacted by KB5065426, which has also been reported.
6. Avoid re-enabling SMBv1, Windows 11 is aggressively removing compatibility layers with every CU, and it will continue breaking after each patch cycle. The long-term fix is ensuring all endpoints speak SMBv2/v3 + NTLMv2 cleanly.

And if this explanation helps you move forward, please consider clicking “Accept Answer” so others running peer-to-peer setups can benefit from it as well 😊.

Jason.