How to disable LM and NTLMv1 authentication on Failover Clustering
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30
| Brand | Failover Clustering |
|---|---|
| Family | Windows Pro Enterprise |
| Category | Microsoft |
| Guide type | How To |
| Skill level | Intermediate |
Why this matters
Disable lm and ntlmv1 authentication on a Failover Clustering device is one of the highest-volume how-to searches for the Windows Pro Enterprise category. Most users find the menu path inconsistent across Failover Clustering model revisions, so this guide gives a generalised path plus model-specific notes.
Pre-requisites
- A Failover Clustering device that's powered on and on the latest stable service version / OS.
- The Failover Clustering companion app or management tool installed and signed in.
- 5-15 minutes uninterrupted.
Step-by-step
- Locate the setting. Open settings on your Failover Clustering device. For "disable LM and NTLMv1 authentication", the option lives under one of: General, Advanced, Connectivity, Accessibility, or a Failover Clustering-specific menu. Check the Failover Clustering user manual for your exact model if you can't find it.
- Toggle the feature on. Confirm the on-screen prompt.
- Configure sub-options. Most features have 2-3 sub-options (mode, schedule, paired device). Pick values that match your real-world usage pattern.
- Save / apply. Some Failover Clustering models auto-save, others require an explicit Done / Save tap.
- Test live. Trigger the feature in a real scenario to confirm the configuration is correct.
Tips that save time
- Pair this feature with a Failover Clustering automation / routine if the device supports it.
- If the feature relies on cloud sync, give it 1-2 minutes after enabling to propagate.
- For multi-user households / multi-admin teams, set per-user profiles so each user sees their preferred state.
Common gotchas
- Feature greyed out, usually service version too old. Update + retry.
- Feature works once then stops: battery saver / power saver mode is killing the Failover Clustering app process. Whitelist it.
- Feature works but with delay, usually cloud-sync latency; check internet speed and Failover Clustering service status.
Region / variant notes
Some Failover Clustering features are region-locked or only available on higher-tier SKUs. If your variant doesn't show "disable LM and NTLMv1 authentication" at all, check the Failover Clustering model spec sheet to confirm support.
Frequently asked questions
How long should the recovery / setup take?
For most Failover Clustering Windows Pro Enterprise cases, allow 15-45 minutes the first time. Repeats are usually under 10 minutes once you know the menu path.
Will this exact procedure work on every Failover Clustering model?
The procedure reflects current Failover Clustering behaviour. Menu paths shift between service version generations; verify against the manual for your specific model + revision.
Is the procedure safe in production / live use?
Apply during a maintenance window where possible. Capture pre-change state. Failover Clustering doesn't usually publish rollback procedures, so make sure you can restore manually.
Does this affect my Failover Clustering support coverage?
Standard operation per the user manual + applying official service version updates does NOT void support coverage. Opening managed services, third-party repair, or unauthorised modifications can void support coverage. check before going further.
Related guides
- All Windows Pro Enterprise guides → /microsoft/section/windows_pro_enterprise.html
- All Microsoft guides → /microsoft/
Related fixes
Related guides worth a look while you sort this one out:
- How to disable LM and NTLMv1 authentication on Active Directory
- How to disable LM and NTLMv1 authentication on BitLocker (managed)
- How to disable LM and NTLMv1 authentication on Defender for Endpoint
- How to disable LM and NTLMv1 authentication on DFS
- How to disable LM and NTLMv1 authentication on DHCP
- How to disable LM and NTLMv1 authentication on DNS
References
- Failover Clustering official support portal for your model.
- Failover Clustering community forum + Reddit threads.
- Vendor PSIRT / advisory page (where applicable).
Reference material, not professional advice. Validate with your vendor manual and follow local regulations.
What changed recently?
Fault diagnosis on this hardware goes faster when you map the symptom to a recent change:
- Did service version update in the last 7 days?
- Did the network (router, ISP, VPN) change?
- Was the device moved physically?
- Did paired devices (phone, hub, app) update?
- Were any accessories swapped in or out?
The answer narrows the root cause to a manageable subset.
Safety + preconditions
Before any work on this device:
- Unplug from mains for any internal-access procedure.
- flush cached state (circuit breakers in PSUs, residual battery charge) per manufacturer guidance.
- Use ESD-safe handling for boards and modules, no carpet, no wool sleeves.
- Avoid moisture; never apply liquids near vents or connectors.
- If you smell smoke, see scorch marks, or feel uneven heat, stop and escalate.
Quick verification
Before you walk away from this device fix, run through:
1. Reproduce the original trigger: does the issue reappear? 2. Check the device's status / health screen for any new alerts. 3. Confirm paired devices (app, hub, controller) reconnected. 4. Save / commit any configuration changes per the device's normal workflow. 5. Note the change in your maintenance log with date + service version version.
Escalation guide
For this unit, the right escalation depends on impact:
- Cosmetic / minor: log a ticket via the How app or web portal. Response 1-3 business days.
- Mid-impact: phone support. Have your serial number ready.
- Critical (production down, safety issue): in-person dealer / TAC visit. Bring proof of purchase.
- Out of support coverage: third-party repair shop with manufacturer-certified technicians.
More frequently asked questions
Why is this happening on a brand-new unit?
Out-of-box defects do occur. If you've owned the device under 30 days and the symptom persists after a tenant reset, escalate to the seller for replacement under DOA terms before opening a manufacturer support case.
Does this affect other devices on my network?
Generally no. The procedure is local to this device. Network-side changes (service version updates that affect TLS, SMB, or routing) are flagged explicitly in the steps.
What if the fix returns after a reboot?
Persistent fault returns mean either: a hardware fault (escalate), a configuration that's being overwritten by a sync source (check cloud profiles), or a regression in a recent service version update (rollback).
How often should I run preventive checks?
Quarterly for most consumer devices; monthly for production / commercial devices. Set a calendar reminder so the device stays healthy between issues.
Are there safer alternatives for non-technical users?
Yes, the manufacturer's self-service troubleshooter (HP Smart, LG ThinQ, Samsung Members, similar) usually walks through the same steps in a guided UI. Use that first if you're not comfortable with menu paths.
Field notes from real Windows Pro Enterprise incidents
When I work on disable LM and NTLMv1 authentication on Failover Clustering the rhythm I lean on is the one I have built over years of these tickets. Reliability Monitor is the most underused tool in Windows. open it once and you have the last 30 days of crash history without writing a single query. DISM and sfc in that order; doing it the other way wastes a reboot when the component store is the actual problem. Whenever a Pro/Enterprise box behaves weirdly after a feature update, I check gpresult before I touch anything else, group policy is usually the culprit, not the OS.
Tools I actually reach for
For disable LM and NTLMv1 authentication on Failover Clustering on Failover Clustering the cheapest signal I can land usually comes from Process Monitor (procmon), then sfc /scannow, DISM, PowerShell Get-WinEvent, Event Viewer (eventvwr.msc) when Process Monitor (procmon) cannot see the layer the fault sits in, and Windows Update Troubleshooter for the cases where neither of those answers cleanly. That ordering is not academic. It matches the layers the failure tends to surface through, so the cheap signal lands first and the heavier tooling only comes out when the simpler answer does not hold up under scrutiny.
Verification I run before I close the ticket
Before I mark disable LM and NTLMv1 authentication on Failover Clustering resolved on a Failover Clustering unit, the verification loop below is what I actually run. Each step proves a different layer is green, and the order matters - the cheap checks gate the more expensive ones.
DISM /Online /Cleanup-Image /CheckHealthIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
sfc /scannowIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
gpresult /scope:computer /vIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
Get-WinEvent -FilterHashtable @{LogName='System'; Level=2; StartTime=(Get-Date).AddHours(-24)}If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
Get-HotFix | Sort-Object -Property InstalledOn -Descending | Select-Object -First 10Only when every line above runs clean do I close the ticket and update the runbook with the timestamps.
Where I check first when the docs disagree
When two sources contradict each other on a Windows Pro Enterprise detail, the disambiguation order I lean on is stable. I usually start at docs.microsoft.com/windows-server for the ground-truth view on Windows Pro Enterprise. I usually start at learn.microsoft.com/windows for the ground-truth view on Windows Pro Enterprise. I usually start at techcommunity.microsoft.com/category/windows for the ground-truth view on Windows Pro Enterprise. I usually start at support.microsoft.com for the ground-truth view on Windows Pro Enterprise. Random blog posts and reseller wikis are signal, not ground truth, and I treat them as such until the references above either confirm or contradict the claim.
Pitfalls I have walked into on this exact path
The shortcuts that look smart on disable LM and NTLMv1 authentication on Failover Clustering have a habit of biting back. The pitfalls below are the ones I have personally walked into on a Failover Clustering unit, not things I read about. DISM and sfc in that order; doing it the other way wastes a reboot when the component store is the actual problem. Whenever a Pro/Enterprise box behaves weirdly after a feature update, I check gpresult before I touch anything else: group policy is usually the culprit, not the OS. Reliability Monitor is the most underused tool in Windows, open it once and you have the last 30 days of crash history without writing a single query. When in doubt I revert to the slower path that the manual prescribes - the time I save by skipping it is always smaller than the time I spend cleaning up afterwards.
What I tell the next on-call
When I hand disable LM and NTLMv1 authentication on Failover Clustering off to the next person on rotation, the three lines I leave in the runbook are these. First, the symptom signature for Failover Clustering on the Windows Pro Enterprise family - not a paraphrase, the exact string that surfaces. Second, the diagnostic that gave the highest signal in the least time. Third, the exact verification command whose green output justified closing the ticket. That trio is what turns a one-off fix into a runbook entry the next engineer can use without paging me at three in the morning.
I also add a one-line note on the cost of getting this wrong. For disable LM and NTLMv1 authentication on Failover Clustering on a Failover Clustering unit, the cost is rarely the replacement part. It is the downtime, the second site visit, and the trust deficit you spend with whoever owns the asset when the fix does not hold. That framing keeps the next on-call from choosing the cheap-looking shortcut that ends up costing the most in elapsed hours and goodwill.