Windows 11 Won’t Install? Fixes That Work

If Windows 11 won’t install on your PC, the cause is almost always a hardware compatibility check failure, a corrupted download, or a BIOS setting that needs changing. Start by running the PC Health Check app, then work through the fixes below in order—most people resolve the issue by enabling TPM 2.0 and Secure Boot in the BIOS, or by installing the latest Windows updates first.

Why Windows 11 Has Strict Requirements

Windows 11 introduced a much higher hardware bar than Windows 10. Microsoft designed it with security and performance in mind, which is why it demands a 64-bit processor with at least 1 GHz and 2 cores, 4 GB of RAM, 64 GB of storage, and a DirectX 12 compatible GPU. The two most common blockers are TPM 2.0 (a security chip) and Secure Boot (a firmware feature). Many older PCs have these but they are disabled in the BIOS, so Windows Setup simply reports the PC as incompatible.

Another frequent issue is that the PC Health Check app gives a generic “This PC doesn’t meet the minimum system requirements” message without telling you which specific component fails. That vague message leads people to believe their hardware is too old when a simple BIOS toggle would fix it.

Step 1: Run the PC Health Check App

Before changing anything, download and run the official PC Health Check app from Microsoft. It will tell you whether your CPU, RAM, storage, TPM, and Secure Boot meet the requirements. If it says you’re incompatible, click “See all results” to see which item fails. Write that down—it determines which fix you need.

If TPM is the problem: Go to your BIOS and enable “Intel Platform Trust Technology” (Intel) or “AMD fTPM” (AMD).
If Secure Boot is the problem: Enter BIOS, find “Boot” or “Security” settings, and set “Secure Boot” to Enabled (or “Windows UEFI mode”).
If the CPU is not on the supported list: Check if your processor is on Microsoft’s official Windows 11 supported CPU list. If not, you may need to install via the ISO method (see below).

Step 2: Enable TPM 2.0 and Secure Boot in BIOS

TPM 2.0 and Secure Boot are often disabled by default on desktops and older laptops. To enable them, restart your PC and press the BIOS key during boot—usually Del, F2, F10, or Esc. The exact key appears on the first screen.

Enter the BIOS/UEFI setup.
Look for a “Security” or “Trusted Computing” section.
Enable “TPM 2.0” (Intel) or “AMD fTPM” (AMD).
Go to “Boot” or “Boot Options” and enable “Secure Boot”. If you don’t see Secure Boot, your PC may be in Legacy BIOS mode—switch to UEFI mode first.
Save and exit (usually F10).

After enabling these, restart and run the PC Health Check again. If Secure Boot is greyed out, you may need to set a BIOS administrator password first, or your drive might be formatted as MBR instead of GPT. Converting to GPT is more advanced and usually requires reinstalling Windows, so consider that a last resort.

Step 3: Update Windows and Drivers First

If your hardware is compatible but the installation still fails, outdated Windows 10 updates or drivers are often the culprit. Windows Setup needs the latest servicing stack to handle the upgrade properly.

Go to Settings > Update & Security > Windows Update and click “Check for updates”. Install all pending updates, including optional ones.
Update your graphics, chipset, and storage drivers from the manufacturer’s website (not just Device Manager).
Uninstall any third-party antivirus temporarily—some security software interferes with the upgrade.

After updating, restart and try the Windows 11 installation again. A clean update history reduces the chance of a rollback mid-install.

Step 4: Free Up Disk Space and Check Storage

Windows 11 needs at least 64 GB of free space, but the upgrade process may require more for temporary files. If you’re low on space, the installer will fail with an error like “0x80070070” or simply stop.

Open Settings > System > Storage and see how much free space you have.
Use Disk Cleanup to remove temporary files, or uninstall large programs you don’t use.
If you have an external drive, you can move personal files there temporarily.
Check that your system drive is healthy—run chkdsk /f in an elevated Command Prompt.

Also, make sure your PC is plugged into power during the install—a laptop that dies mid-upgrade can corrupt the system.

Step 5: Use the Windows 11 Installation Assistant or ISO

If Windows Update won’t offer the upgrade, use the Windows 11 Installation Assistant from Microsoft’s website. It downloads the full installer and runs the upgrade directly. If that fails, download the Windows 11 ISO and mount it (double-click), then run setup.exe.

For PCs that don’t meet the requirements but are otherwise capable, Microsoft allows installation via the ISO method—but it’s unsupported and you won’t receive future updates. If you choose this route, you’ll need to bypass the TPM and CPU checks by editing the registry or using a modified setup. That’s risky and not recommended for most users.

Common Error Codes and What They Mean

Windows 11 installation errors often come with a code. Here are the most common ones and their fixes:

0x80070070 – Not enough disk space. Free up space as described above.
0x800F0923 – Driver or software incompatible. Update all drivers and uninstall conflicting apps.
0x8007007E – A driver or service failed. Run the Windows Update troubleshooter and try again.
0xC1900101 – Driver failure during install. Uninstall non-essential hardware (like a second GPU) and update drivers.
0x80300024 – Boot configuration error. Check that your disk is GPT and Secure Boot is enabled.

If you see a generic error with no code, check the Windows Setup log files in C:\$Windows.~BT\Sources\Panther for more detail.

What to Do If Nothing Works

If you’ve tried all the above and Windows 11 still won’t install, consider these final options:

Reset Windows 10: Go to Settings > Update & Security > Recovery and “Reset this PC”. Choose “Keep my files” and reinstall Windows 10 fresh, then try the upgrade again.
Clean install: Back up your data, create a Windows 11 bootable USB using the Media Creation Tool, and boot from it. Wipe the drive and install from scratch. This bypasses many upgrade-specific issues.
Check your hardware: If your CPU is older than 2017 or your RAM is less than 4 GB, Windows 11 simply won’t run well. Consider upgrading your PC or sticking with Windows 10, which is supported until October 2025.

Remember that installing Windows 11 on unsupported hardware is possible but unsupported—you may miss security updates and encounter driver issues. For most people, a clean install is the most reliable path.

Frequently Asked Questions

Why does my PC say “TPM 2.0 must be supported and enabled”?

Your PC has a TPM chip but it’s turned off in the BIOS. Enter your BIOS and look for “Intel Platform Trust Technology” or “AMD fTPM” and enable it. If you don’t see it, your motherboard may need a BIOS update from the manufacturer.

Can I install Windows 11 without TPM 2.0?

Yes, but only by bypassing the check during installation—usually via a registry tweak or a modified setup. This is unsupported and you won’t get updates. It’s not recommended for everyday use.

Why does the installation stop at 99%?

This usually happens due to a driver conflict or a corrupted download. Uninstall any third-party antivirus, update your drivers, and try using the Installation Assistant instead of Windows Update.

Do I need to enable Secure Boot if I have a UEFI system?

Yes, Windows 11 requires Secure Boot. If it’s disabled, enable it in BIOS. If you don’t see the option, your system might be in legacy BIOS mode—switch to UEFI mode and convert your disk to GPT.

How long does a Windows 11 installation take?

Typically 20-60 minutes depending on your hardware and internet speed. If it takes longer than 2 hours, something is wrong—check for error codes and restart the installation.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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