What is the difference between DISM and SFC, and which should I run first?

DISM (Deployment Image Servicing and Management) repairs the Windows component store — the repository of Windows files used during installations and updates. SFC (System File Checker) repairs individual system files by replacing them from the component store. Run DISM first because SFC uses the component store as its repair source — if the component store is corrupted, SFC cannot repair anything correctly. Always run DISM, then SFC, then restart.

My Windows 11 installation fails with error 0xc1900101 — what does this mean?

Error 0xc1900101 is a driver rollback error. During installation, a hardware driver failed to initialize in the new Windows environment and Windows rolled back to protect your system. The fix is to identify the failing driver in Device Manager (look for yellow warning triangles), update it from the manufacturer's website, or roll it back if it was recently updated. See the dedicated guide: /computers/windows-update-error-0xc1900101-fix/

Can I check if my PC supports Windows 11 before attempting installation?

Yes. Download the PC Health Check app from microsoft.com/windows/windows-11 and run it. It checks all hardware requirements — TPM 2.0, Secure Boot, CPU compatibility, RAM, and storage — and lists exactly which requirements are not met. This is the most reliable way to identify compatibility blocks before attempting the installation.

How do I know if DISM successfully repaired my Windows component store?

DISM reports its result at the end of the scan. A successful repair shows: 'The restore operation completed successfully.' If DISM reports it cannot repair the component store because it cannot contact Windows Update, check your internet connection and run the Windows Update Troubleshooter first. You can also view the DISM log at C:\Windows\Logs\DISM\dism.log for detailed information about what was repaired.

Windows 11 installation fails at a specific percentage — is that significant?

Yes. Failures at specific points can narrow the cause: failures at 0–30% typically indicate a download or component store issue (DISM fixes this); failures at 30–75% suggest a driver conflict during file copying (check Device Manager); failures at 75–99% indicate a problem during the post-restart configuration phase, often related to TPM or Secure Boot settings. The error code in Update history gives the definitive diagnosis.

Windows 11 Installation Fails — Fix

Windows 11 installation fails when the upgrade or cumulative update begins — the download completes, but the installation stops partway through and Windows rolls back to the previous state. According to Microsoft’s official documentation, the most common causes are a corrupted Windows component store, driver conflicts that interrupt the installation process, and missing hardware requirements like TPM 2.0 or Secure Boot.

Windows 11 installation fails — fix steps: check error code, run DISM, run SFC, update drivers, verify TPM and Secure Boot

What causes Windows 11 installation to fail

Windows 11 installation modifies the Windows Component Store (C:\Windows\WinSxS) — the repository of all Windows files. If this store has corrupted entries, the installation cannot complete. Other causes:

Corrupted Windows component store — the primary cause of mid-installation failures with no obvious error
Driver conflicts — a hardware driver (display, network, chipset) cannot initialize in the new Windows environment
TPM 2.0 not enabled or not detected — Windows 11 enforces TPM 2.0 during installation, not just at the start
Secure Boot disabled or in Legacy mode — the installation requires UEFI firmware with Secure Boot enabled
Insufficient disk space — installation needs at least 10 GB free for cumulative updates, 20+ GB for version upgrades
Corrupted individual system files — files that the installation needs to replace are already damaged

How to fix Windows 11 installation fails

Step 1 — Note the error code from Update history

Before applying any fix, record the exact error code — it determines the correct solution and saves time.

Go to Settings → Windows Update → Update history
Find the failed installation entry and click to expand it
Note the error code (for example, 0x800f0922, 0xc1900101, 0x8007001f)

If no code appears in Update history:

Press Win + S, search for Event Viewer, and open it
Expand Windows Logs → System
Click Filter Current Log → set Source to WindowsUpdateClient
Find entries near the time of the failure — the error code appears in the Event description

With the error code recorded, the steps below give you the most targeted fix.

Step 2 — Run DISM to repair the Windows component store

DISM is the correct tool for installation failures because it repairs the component store — the exact resource that installation modifies.

Open Command Prompt as administrator and run:

DISM /Online /Cleanup-Image /RestoreHealth

DISM contacts Windows Update servers to download replacement files. This takes 15–30 minutes. The progress counter may pause at 20%, 65%, or other points — this is normal behavior. Do not close the window or shut down the PC.

When complete, DISM reports: “The restore operation completed successfully.”

If DISM cannot connect to Windows Update, add /Source to specify a local source, or check your internet connection and run the Windows Update Troubleshooter first.

Step 3 — Run SFC after DISM completes

After DISM repairs the component store, SFC repairs individual system files using that now-repaired store as its source. Running SFC before DISM may produce incorrect results if the store itself is corrupted.

In the same administrator Command Prompt, run:

sfc /scannow

SFC scans all protected Windows system files. When complete, it reports one of:

“Windows Resource Protection did not find any integrity violations” — no additional repair needed
“Windows Resource Protection found corrupt files and repaired them” — files were repaired

After SFC completes, restart your PC, then go to Settings → Windows Update → Check for updates and retry the installation.

Step 4 — Update or roll back drivers in Device Manager

Driver conflicts cause installation rollback — the installation applies successfully until a driver component fails, triggering an automatic rollback.

Right-click Start → Device Manager
Look for devices with a yellow warning triangle (!)
Right-click each flagged device → Update driver → Search automatically for drivers
For display adapters, network adapters, and chipset drivers — visit the manufacturer’s website for the latest version even if Device Manager shows no warning:
- NVIDIA/AMD/Intel graphics: nvidia.com, amd.com, intel.com
- Network adapters: motherboard or laptop manufacturer’s support page
If any driver was recently updated before installation failures began: right-click the device → Properties → Driver tab → Roll Back Driver

After driver changes, restart your PC, then retry the installation.

Step 5 — Verify TPM 2.0 and Secure Boot are enabled

Windows 11 enforces TPM 2.0 and Secure Boot during installation. If either is disabled, the installation will fail — sometimes partway through rather than at the start.

Check TPM status:

Press Win + R, type tpm.msc, press Enter
Confirm Status: The TPM is ready for use and Specification Version: 2.0
If TPM shows version 1.2 or “Not Found”: restart and enter BIOS/UEFI (typically Del, F2, or F10 — shown briefly during startup)
Find the Security or Trusted Computing section and enable:
- Intel systems: PTT (Platform Trust Technology)
- AMD systems: fTPM (Firmware TPM)

Check Secure Boot:

In BIOS/UEFI, navigate to the Boot section
Confirm Secure Boot: Enabled
Confirm the firmware mode is UEFI (not Legacy or CSM)

Save all changes and exit BIOS/UEFI. After restarting, retry the Windows 11 installation.

How to verify the fix

Go to Settings → Windows Update → Update history
Confirm the previously failing entry now shows Successfully installed
Check Settings → System → About — the Windows 11 version number confirms the upgrade completed

If installation still fails after completing all five steps, consult the Windows 11 Upgrade Errors hub for error-code-specific guides, or contact Microsoft Support at support.microsoft.com with the exact error code from Update history.