How to fix error 0x0000009f in Windows 11

Solution Steps

1. 1 Press Windows key + X and select 'Device Manager'. Expand categories like 'Display adapters', 'Network adapters', and 'Storage controllers'. For each device, right-click and select 'Properties'. Go to the 'Power Management' tab and uncheck 'Allow the computer to turn off this device to save power'. This prevents drivers from entering a problematic power state.
2. 2 Press Windows key + I to open Settings, then go to System → Power & battery → Screen and sleep. Set 'Sleep' to 'Never' temporarily to see if the error stops. If it does, the issue is with sleep mode.
3. 3 Update your drivers. Go to Settings → Windows Update → Advanced options → Optional updates. Install any driver updates. Also visit your hardware manufacturer's website for the latest drivers, especially for your chipset and graphics card.
4. 4 Press Windows key + R, type 'powercfg /energy', and press Enter. This runs a 60-second energy report that identifies power-related issues. The report is saved as an HTML file in your user folder (e.g., C:\Users\YourName\energy-report.html). Open it and look for errors or warnings related to drivers.
5. 5 If the error occurs during sleep/wake, disable fast startup. Go to Control Panel → Power Options → Choose what the power buttons do → Change settings that are currently unavailable → Uncheck 'Turn on fast startup' and save changes. Fast startup can cause driver issues.
6. 6 Run 'sfc /scannow' and 'DISM /Online /Cleanup-Image /RestoreHealth' as administrator to repair system files that might be causing driver issues.