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WHEA_UNCORRECTABLE_ERROR

WHEA_UNCORRECTABLE_ERROR (0x124) on Windows: the hardware reported an error it could not correct

Verified with sources2 sourcesReviewed Oct 3, 2026
Technician coming? See the 2 steps they must show you

Risk level

High

Professional inspection is recommended.

Urgency

High

Quick answer

The hardware itself reported a severe error to Windows that it could not correct. If you enabled over-clocking, turn it off; check that fans spin and vents are clear, and have the PC checked if it repeats.

Safety first

Stop and check this first

  • Although Microsoft links it to hardware, 0x124 alone does not say which part is failing. Do not accept a CPU, motherboard or memory replacement without the WHEA record and a confirming test.
  • Do not open the case or the power supply to clean or inspect internal fans unless you know how; that is technician work.

Safe checks you can perform

  • Over-clocking and performance settings
  • Fans and vents without opening the PC
  • System event log

Leave these tasks to a qualified professional

  • Do not attempt this professional task: Read the WHEA error record
  • Do not attempt this professional task: Hardware and cooling diagnostics

What a technician must be able to justify

A technician is coming

These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.

These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.

  1. Read the WHEA error record

    What they doIT support uses !analyze -v and !errrec with the parameter 2 address, or !whea and !errpkt, to see which source and component reported the error.

    They must show youthe parameter 1 error type and the component in the record.

    In writingwhich component was flagged and which test confirmed it.

  2. Hardware and cooling diagnostics

    What they doThey run memory and system diagnostics and check fans and cooling inside the PC.

    They must show youtest results and cooling condition.

    In writingwhat failed and, if a part is replaced, its reference and reason.

Before accepting a part or repair

Nothing has been shown yet. Do not accept a part swap based on the code alone.

Checks and evidence, step by step

Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.

  1. 1

    Over-clocking and performance settings

    No special tools

    Procedure

    Who:
    you.
    How:
    if you enabled over-clocking in UEFI (BIOS) or with a maker's utility, restore the defaults.
    Result that matters:
    whether blue screens stop with defaults.
    If they stop:
    over-clocking caused it; do not turn it back on.
    If they continue or you never enabled it:
    move on to cooling.
    Evidence to keep:
    which setting you had and when you removed it.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  2. 2

    Fans and vents without opening the PC

    No special tools

    Procedure

    Who:
    you.
    How:
    with the PC on, listen and feel with your hand that air comes out of the vents; switch it off and remove visible dust from the outside vents without opening the case.
    Result that matters:
    whether a fan does not spin or the vents were blocked.
    If one does not spin or vents were blocked:
    heat is a candidate; take the PC to a technician.
    If air flows normally:
    internal heat is not ruled out, but there is no outside sign.
    Evidence to keep:
    a note of what you saw and when the blue screens happen.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  3. 3

    System event log

    No special tools

    Procedure

    Who:
    you.
    How:
    in Event Viewer open Windows Logs, System, and look for hardware error events at the time of the blue screen; Microsoft says the error record is saved in the system event log.
    Result that matters:
    whether hardware error events exist and which component they name.
    If they exist:
    keep them; they are what the technician needs.
    If none appear:
    the memory dump will be the source.
    Evidence to keep:
    export or screenshot of the events.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

Where this code applies

A code is meaningful only inside the right product and version context.

Primary scope

System
Software and systems
Brand
Microsoft Windows
Product type
Operating system

Known code variants

  • 0x00000124
  • 0x124
  • STOP 0x00000124
  • stop code WHEA_UNCORRECTABLE_ERROR
  • WHEA UNCORRECTABLE ERROR

What it means

Microsoft defines 0x00000124 as a fatal hardware error reported through the Windows Hardware Error Architecture (WHEA). Parameter 1 gives the type of error source (machine check exception, PCI Express error, generic error and others) and parameter 2 the address of the error record, which is also saved in the event log. It is typically related to physical failures, heat, memory or the processor; less likely, to a driver. The code does not say which part.

Warnings and stop conditions

  • Higheditorial warning

    Although Microsoft links it to hardware, 0x124 alone does not say which part is failing. Do not accept a CPU, motherboard or memory replacement without the WHEA record and a confirming test.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  • Mediumeditorial warning

    Do not open the case or the power supply to clean or inspect internal fans unless you know how; that is technician work.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

Symptoms and causes

Probable causes · in order

  • Heat or insufficient coolingPossible

    Microsoft asks you to confirm the fans work. Suspected if crashes happen under load or when the PC is hot.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  • Over-clocking enabledPossible

    Microsoft recommends disabling it; if crashes stop with defaults, that was the cause.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  • Memory or processor starting to failPossible

    Microsoft lists it as a typical cause; only diagnostics and the WHEA record point to the component.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

  • Driver causing the hardware to failLess common

    Microsoft considers this less likely but possible.

    Evidence: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

Virtual technician

Does WHEA_UNCORRECTABLE_ERROR still appear after these checks?

Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.

Start diagnosis

Sources and technical references

  1. 1

    Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR

    Microsoft · 2026 · official_doc

  2. 2

    Troubleshooting Windows unexpected restarts and stop code errors

    Microsoft · 2026 · official_doc

Sources: Bug Check 0x124 WHEA_UNCORRECTABLE_ERROR · Troubleshooting Windows unexpected restarts and stop code errorsreviewed 2026-10-03 · verified

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