Code 43: Is It a Driver Problem or Hardware Failure

Code 43 means CM_PROB_FAILED_POST_START: Windows has stopped this device because it has reported problems. I sort it by symptoms first: a device-specific failure usually points to hardware or connection trouble, while broad instability often points to drivers. The fastest first check is Device Manager: open Win+X > Device Manager, find the device with the yellow warning icon, and note what changed right before the error appeared. (Microsoft Support) (Microsoft Learn)

What usually causes code 43?

Possible causes include a bad driver update, corruption in a loaded driver, or a hardware or connection problem with the affected device. Reported guidance also notes that one of the drivers controlling the device may have notified Windows that the device failed in some manner. For GPUs, code 43 can also mean the drivers are bad or the GPU is not connected properly, as reported by bleepingcomputer.com.

How to inspect the failure pattern first

1. Open Win+X > Device Manager.
2. Expand the device category, or check View > Show hidden devices if the hardware vanished after sleep or an update.
3. Right-click the affected device > Properties > check the General tab for the status text and the Driver tab for Update driver, Roll Back Driver, Uninstall Device, and version details.
4. If the device is a GPU, USB device, Bluetooth radio, or Wi‑Fi adapter, note whether the problem began after a driver install, a resume from sleep, or a move to another port.

Ranked causes to keep in mind

Driver trouble comes first. Microsoft’s device-manager reference identifies code 43 as CM_PROB_FAILED_POST_START, and reported guidance says one of the drivers controlling the device may have told Windows that the device failed. The same reported guidance also says corruption in one of the loaded drivers can cause the error and that the driver cache may just need to be flushed. (manageengine.com)

Connection or power trouble comes next. USB devices and external radios can fail because of a bad connection path or a bad USB state. For GPUs, reported guidance says code 43 can mean drivers are bad or the GPU is not connected properly.

Hardware failure moves up the list after basic checks fail. When the same device still fails after driver cleanup and simple connection checks, testing it in another compatible system becomes the fastest way to separate the PC from the device.

According to How to Resolve Error Code 43 for Intel® Graphics — Intel says code 43 can be caused by hardware problems or driver or settings corruption. (source)

Use this decision table before you change anything

The best next step depends on the device type and what happened right before code 43 appeared. Use the pattern below to pick the first branch. If the table points to hardware testing elsewhere, stop software work on the current PC there.

Device-type decision table

How do you fix code 43 when the cause is a bad driver?

Start with timing. If code 43 began after Windows Update, a vendor installer, or a manual driver swap, treat it as driver trouble first. Roll back when the old version worked. If rollback is unavailable or fails, remove the device and install the correct OEM driver before Windows Update gets a turn.

Rollback first when the break has a clear timestamp

1. Open Win+X > Device Manager > right-click device > Properties > Driver.
2. Select Roll Back Driver if the button is available.
3. Do a full reboot, then recheck Device Manager.
4. If Roll Back Driver is greyed out, go to the uninstall steps below.

Uninstall and force redetection

1. Open Win+X > Device Manager > right-click device > Uninstall device.
2. If shown, check Delete the driver software.
3. Restart the PC. After Windows loads, open Device Manager, select the computer name at the top, then choose Action > Scan for hardware changes.
4. If the device returns with code 43, shut the PC down completely, start it again, then install the proper OEM driver package from the system maker or device maker.

Use Windows Update after the clean reinstall, not before it

1. For Windows 11, open Settings > Windows Update. For Windows 10, the path is the same, though Microsoft’s main fix page applies to Windows 10.
2. Install the OEM or system-maker driver first if the device is a GPU or wireless adapter.
3. Only after that, run Settings > Windows Update > Check for updates to pick up compatibility fixes or remaining components.

How do you fix code 43 on a GPU?

For a GPU, the safest branch is a clean install using the system manufacturer or graphics-card manufacturer package, not the first driver Windows offers. If the adapter falls back to Microsoft Basic Display Adapter after uninstall, that is expected during cleanup. Repeated code 43 after a proper clean reinstall points away from software.

Clean GPU reinstall path

1. Download the correct GPU driver from the laptop maker, motherboard maker, or graphics-card vendor before removing anything.
2. If the GPU is Intel-based, Intel recommends a clean install of the latest graphics drivers provided by the system manufacturer, disconnecting from the Internet so Windows will not automatically update the driver, and uninstalling both the Intel Graphics driver and the Intel Display audio driver.
3. Open Win+X > Device Manager > Display adapters > right-click the GPU > Uninstall device. Check Delete the driver software if present.
4. Restart. The device may appear as Microsoft Basic Display Adapter after uninstall, which Intel notes is normal during this stage.
5. Install the downloaded OEM package, restart, then verify the driver version in Properties > Driver.

What about NVIDIA searches and repeated failures?

The same logic applies to NVIDIA code 43 searches: a recent driver break calls for rollback or a clean reinstall first, then hardware checks. Reported guidance from bleepingcomputer.com recommends uninstalling the drivers with Display Driver Uninstaller, then reinstalling them first. If code 43 returns right after a clean reinstall, stop spending time on software and test the card elsewhere.

How do you fix code 43 on USB, Bluetooth, or Wi‑Fi devices?

USB, Bluetooth, and Wi‑Fi code 43 cases split fast once the symptom pattern is clear. USB usually points to the connection path or a bad USB state. Bluetooth and Wi‑Fi often point to the OEM wireless package. Start with the shortest hardware path before you touch drivers.

USB: ports, cables, and a hard power reset

1. Move the device to a direct rear motherboard USB port for the first test. Do not use a front-panel port, hub, or dock for that check.
2. If the device uses a removable cable, replace it with another known-good cable.
3. Test the USB device on another USB port on the same PC, then on another PC if one is available.
4. If the issue started after a bad USB state, follow the hard power reset path reported by learn.microsoft.com: unplug all of your USB devices, turn off the PC and take out the battery if the battery is removable, let the PC set for about 5 minutes, then put the battery back in and restart the PC. After restart, plug your USB devices back in one at a time and make sure that they work. Reported guidance notes that unplugging the computer sometimes does not resolve the problem because the battery still holds power, and if that does not work or you are on a desktop, follow the steps in this KB article.

Bluetooth: stale devices and radio reset

1. Open Win+X > Device Manager > Bluetooth.
2. Right-click the radio > Disable device, wait a moment, then Enable device.
3. Open Settings > Bluetooth & devices and remove pairings that no longer connect.
4. Back in Device Manager, remove the Bluetooth adapter, use Action > Scan for hardware changes, then install the OEM Bluetooth or wireless package from the PC maker’s support page.

Wi‑Fi: OEM package reinstall

1. Open Win+X > Device Manager > Network adapters > right-click the Wi‑Fi adapter > Properties > Driver.
2. If the issue began after an update, use Roll Back Driver.
3. If not, choose Uninstall device. If Delete the driver software appears, check it. Shut the PC down fully, start it again, then install the laptop or motherboard maker’s wireless package.
4. After the OEM package finishes, run Settings > Windows Update > Check for updates.
5. Test after a full shutdown and fresh start, then test again after sleep. If the error appears only after resume, that points to how the adapter is returning from a power state rather than proving the adapter is dead.

When BIOS, firmware, or Windows tools are worth trying

Windows repair tools belong later in the ladder, after the correct driver and hardware-path checks. Use them when code 43 keeps coming back after a clean reinstall or when you want to rule out broader Windows corruption.

Firmware and BIOS branch

1. If your PC or device maker provides a firmware update specifically for the affected hardware, read the release notes on the manufacturer support page for your exact model.
2. Install only the update provided for that exact model and follow the manufacturer’s instructions while the system is on AC power.
3. After updating, load Windows normally and recheck the device in Device Manager before reinstalling anything else.

Windows tools that fit this workflow

1. Run the Windows Update troubleshooter: ms-settings:troubleshoot, then open Other troubleshooters and run the relevant tool.
2. Run the Hardware and Devices troubleshooter if it is available in the broader device workflow on the system.
3. Open Command Prompt as Administrator and run sfc /scannow. (dell.com)
4. If SFC finds corruption or the issue still returns, run DISM /Online /Cleanup-Image /RestoreHealth, restart, then retest. (superops.com)

Still not working? When to test elsewhere or replace the device

Stop after the device has failed the same way through a clean reinstall, a direct connection path, and at least one outside check such as another port or another PC. At that point, repeated code 43 fits failing hardware far better than ordinary Windows corruption.

If that did not work, use this escalation ladder

1. For a USB device, test it with a different known-good cable if it uses one, then test it on another PC.
2. For a Wi‑Fi or Bluetooth adapter, test after a full shutdown and restart, then test again after sleep. If only resume triggers the error, reinstall the latest OEM wireless package before replacing hardware.
3. For a desktop GPU, power the PC off, switch the PSU off if present, reseat the graphics card, and make sure every required PCIe power lead is fully connected. Then test the card in another compatible system if possible.
4. If the same hardware keeps triggering code 43 across multiple ports, cables, or systems, it is reasonable to move to repair, RMA, or replacement instead of repeating software fixes.
5. If the PC works normally with a substitute device of the same type but the original hardware still throws code 43, treat the original part as the fault.

Prevention

Once the device is working again, keep a copy of the known-good OEM driver package and pause unnecessary manual driver swaps. For GPUs and wireless adapters, that one habit prevents a lot of repeat code 43 cases on Windows 11.

Frequently asked questions

Why does Device Manager show code 43?

Device Manager shows code 43 when the device or its driver stack fails during start and Windows stops it. In practice, the first split is timing: if the error began after a driver change, check Properties > Driver > Roll Back Driver; if it began after a cable, port, or USB-state event, check the connection path first.

Is code 43 a driver problem or hardware failure?

It can be either. Driver trouble is the first branch when the device worked until an update or reinstall. Hardware failure moves ahead when code 43 returns right after a clean reinstall, follows the device to another PC, or stays with the same hardware across multiple ports and cables.

How do you fix code 43 on Windows 11?

On Windows 11, open Win+X > Device Manager, inspect the device’s Driver tab, and use rollback if the timing fits. If not, remove the device, scan for hardware changes, install the OEM driver, then run Settings > Windows Update > Check for updates.

How do you fix code 43 on an NVIDIA GPU?

Treat it as a GPU triage case rather than a brand-only issue. If a new NVIDIA driver started the problem, roll back in Device Manager > Display adapters > GPU > Properties > Driver. If that fails, clean-uninstall, reinstall the correct vendor package, and if code 43 still returns right away, test the card in another system.

Can code 43 be fixed without replacing the device?

Yes, often. Driver corruption, bad updates, and USB connection-state problems can all produce code 43 without dead hardware. Replacement becomes the practical next step only after the device repeats the same failure after clean reinstall, direct-connection testing, and another known-good system or cable path.

What is Error Code 43 on Mac and what causes it?

Mac error 43 is a different issue and should not be mixed with Windows Device Manager code 43. If the problem is on Windows, stay inside Device Manager, OEM drivers, connection checks, and Windows repair tools. If the problem is on macOS, use Mac-specific file-system guidance instead of Windows hardware triage.

Should I buy a GPU with error 43?

Only as a repair gamble. A GPU that already throws code 43 may recover with a clean driver install, but repeated code 43 after driver cleanup and a second PC is a bad sign. Unless the price assumes possible failure and there is no warranty path, it is usually a poor buy.