Windows 11 won't start: how to use Startup Repair

2 min read · 7 steps · Updated 3 October 2026

Short answer

Open the Windows Recovery Environment: after two or three failed starts it appears by itself, or hold Shift while you click Power, Restart. Choose Troubleshoot, Advanced options, Startup Repair and then Restart. Windows scans for damaged start-up files and repairs what it can.

When Windows hangs at the logo, restarts in a loop or shows a blue recovery screen, the files it needs for starting are often damaged, for example after a power cut or an interrupted update. Startup Repair is the built-in tool for exactly that. It does not touch your personal files.

These steps are for Windows 11. The pictures are simplified diagrams, not screenshots, so colours and spacing on your PC look a little different.

Step by step

  1. Get into the recovery environment

    If Windows fails to start correctly several times in a row, it opens the blue recovery environment by itself. You can force this: switch the PC on, and as soon as the Windows logo appears, hold the power button until it turns off. Do that two or three times.

  2. – ▢ ✕SettingsSystemBluetooth & devicesNetwork & internetAppsAccountsTime & languageAccessibilityWindows UpdateSystemActivationTroubleshootRecoveryProjecting to this PC

    Or open it from a working Windows

    If Windows still starts but behaves badly, open Start, Settings, System, Recovery and click Restart now next to Advanced startup. Or hold the Shift key while you click Power, Restart.

  3. Choose Startup Repair

    On the blue screen, select Troubleshoot, then Advanced options, then Startup Repair. Click Restart if asked, and pick your account.

  4. Enter the BitLocker key if asked

    On an encrypted drive, Windows asks for the 48-digit BitLocker recovery key. It is stored in your Microsoft account: on another device, sign in at account.microsoft.com/devices/recoverykey.

  5. Let it run

    The tool checks for missing or damaged system files, damaged boot data and faulty drivers, and tries to repair them. This can take from a few minutes to more than half an hour. Then the PC restarts.

  6. If it could not repair the PC

    Go back to Advanced options. Uninstall Updates removes the latest update, which helps when the trouble began right after one. System Restore returns Windows to an earlier restore point. Startup Settings leads to safe mode.

  7. Last resort: Reset this PC

    Under Troubleshoot, Reset this PC reinstalls Windows. Choose Keep my files to keep your documents. Programs have to be installed again.

Good to know

If the recovery environment itself will not open, create Windows installation media on a USB stick with another PC, start from it and choose Repair your computer.

A PC that does not show even the manufacturer logo, or reports no boot device, may have a hardware fault, often the drive. That is a job for a repair shop.

Step by step: how to start Windows 11 in safe mode, how to use System Restore and how to factory reset a Windows 11 PC.

Related: Windows 11 black screen: 8 fixes to try, Windows 11 blue screen and Windows 11 update failed or stuck.

In short: Recovery environment (automatic after failed starts, or Shift with Restart), Troubleshoot, Advanced options, Startup Repair. Then Uninstall Updates, System Restore, and Reset this PC as the last step.

Sources
  • Microsoft Support: Startup Repair
  • Microsoft Support: Windows Recovery Environment

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