Windows 11 Boot Loop: How to Stop a Restart Loop for Good

A Windows 11 boot loop is when the PC starts, shows the logo or a spinning circle, and then restarts again before you reach the desktop, over and over. Sometimes it cycles through “Preparing Automatic Repair” and “Diagnosing your PC” without ever fixing anything; sometimes it flashes a blue screen for a split second. The good news is that Windows 11 (24H2 and 25H2, Home and Pro) has a built-in recovery environment designed for exactly this, and most loops can be broken without losing files.

Work through the sections in order. Each step is less disruptive than the next.

Common causes of a restart loop

Symptom	Likely cause
Loop started right after Windows Update	A quality or feature update did not install cleanly
Loop started after installing a driver or new hardware	Incompatible driver or device
Brief blue screen, then restart	A stop error; the code tells you which driver or component failed
“Preparing Automatic Repair” over and over	Damaged startup files, disk errors or a driver crashing early
Restarts even before the maker’s logo	Power, memory, overheating or firmware, not Windows

Step 1: Rule out devices and the update itself

1. Unplug everything you do not need. Remove USB sticks, memory cards, external drives, docks, printers and game controllers. A bootable USB stick or a faulty device can send the firmware down the wrong path.
2. Undo new hardware. If you added memory, a graphics card or a drive just before the loop began, remove it and test again.
3. Check whether it is really a loop. If the screen says “Working on updates” or “Undoing changes”, Windows may restart several times on its own. Leave it alone for a while before you intervene.

Step 2: Get into the Windows Recovery Environment

The Windows Recovery Environment (WinRE) is a small repair system on the drive. Windows opens it by itself after it fails to start properly a couple of times. If it does not, trigger it:

1. Turn the PC on. When the maker’s logo appears, hold the power button until the PC turns off.
2. Do this once more.
3. Turn it on a third time and let it run. You should see Automatic Repair. Select Advanced options to reach the blue Choose an option screen.

If WinRE never appears, create a Windows 11 USB drive on another PC (see create a bootable USB), start from it, select Next and then Repair your computer. You get the same tools.

Many PCs have BitLocker or device encryption turned on, so WinRE may ask for the recovery key. Our BitLocker recovery guide explains where it is stored.

Step 3: Read the stop code

If the loop includes a flash of blue, stop Windows from restarting so you can read the error:

1. In WinRE, select Troubleshoot > Advanced options > Startup Settings > Restart.
2. Press 9 or F9 for Disable automatic restart after failure.

Next time Windows crashes, the stop code stays on screen. Write it down; codes that name a file ending in .sys point at a specific driver. The Windows 11 blue screen guide explains the common codes.

Step 4: Startup Repair and Uninstall Updates

From Troubleshoot > Advanced options, try these two tools in turn:

• Startup Repair scans for problems that stop Windows from loading, such as damaged boot files, and fixes what it can. It may take a while and can restart the PC.
• Uninstall Updates offers Uninstall latest quality update (the monthly cumulative update) and Uninstall latest feature update. If the loop began right after Windows Update, remove the matching one. Windows Update will offer it again later, so pause updates for a week or two once you are back in Windows.

Step 5: Use safe mode to remove the culprit

Safe mode loads only basic drivers, so a loop caused by a third-party driver or startup app usually stops there.

1. In WinRE, select Troubleshoot > Advanced options > Startup Settings > Restart.
2. Press 4 or F4 for Safe Mode, or 5 or F5 for Safe Mode with Networking.

Once you are in, undo whatever changed last: roll back the driver in Device Manager (Properties > Driver > Roll Back Driver), uninstall the app from Settings > Apps > Installed apps, or remove an update from Settings > Windows Update > Update history > Uninstall updates. Then repair system files from Terminal (Admin):

1. Run DISM /Online /Cleanup-Image /RestoreHealth (it needs a network connection to download clean files).
2. Run sfc /scannow.

Our safe mode guide has more detail and explains how to leave safe mode again.

Step 6: System Restore and disk checks

System Restore returns system files, drivers and settings to an earlier restore point without touching documents. In WinRE, go to Troubleshoot > Advanced options > System Restore, choose a point from before the loop began and confirm. Apps installed after that point are removed. If you see no restore points, System Protection was turned off on that PC.

If you suspect disk errors, open Command Prompt from the same Advanced options menu and run chkdsk C: /f. In the recovery environment the Windows drive is not always C:. Run dir C:\ first and check that you see the Windows and Users folders; if not, try dir D:\ and use that letter instead.

Step 7: Reset this PC or reinstall

If the loop survives everything above, reinstall Windows:

• Reset this PC in WinRE (Troubleshoot > Reset this PC) reinstalls Windows. Choose Keep my files to keep personal files; apps and settings are removed. Cloud download fetches a fresh copy from Microsoft, which helps when local files are damaged. See our Reset this PC guide.
• Reinstall from USB. Starting from installation media and running a clean install is the next step, but it erases the drive unless you back up first.

When the boot loop is hardware

A loop that continues after a reset or clean install, or that happens before the maker’s logo, is very rarely Windows. Typical culprits are faulty memory, a failing SSD or hard drive, overheating, a weak power supply or a firmware problem. Test memory with Windows Memory Diagnostic if you can reach a working Windows, run the drive maker’s diagnostic, install firmware updates only from the PC maker’s support page for your model, and talk to the maker if the device is under warranty.