Windows 11 on older hardware without TPM 2.0
TPM 2.0 missing, Windows 11 refusing to install? Usually, the chip is just disabled in the BIOS. And for TPM 1.2, there's a method documented by Microsoft itself.
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Short answer: Windows 11 officially requires TPM 2.0 and Secure Boot. There is a registry workaround, documented by Microsoft itself, that allows devices with TPM 1.2 to update. Microsoft explicitly states that updates are not guaranteed on such devices. This is often acceptable for personal computers but not for company computers.
Why Microsoft requires TPM at all
The Trusted Platform Module is a small chip on the motherboard that stores keys separately from the processor. Windows 11 uses it for BitLocker, Windows Hello, and credential protection. Together with Secure Boot, it is intended to prevent malicious code from embedding itself before the system starts.
This is not harassment but a reaction to a real class of attack. Nevertheless, the requirement excludes many computers that are technically perfectly sufficient.
First check: do you really not have TPM?
Many devices have a TPM, but it is just disabled in the BIOS. Before bypassing anything, check the current status:
- Press Windows key + R, type
tpm.msc. - If it shows specification version 2.0, everything is fine, and Windows 11 will run regularly.
- If the window reports that no TPM was found, check the BIOS. For Intel, the option is usually called PTT (Platform Trust Technology), for AMD, fTPM. Both are often disabled by default.
This step, based on experience, solves the problem in a large number of cases, without any intervention.
The documented method for TPM 1.2
If your computer only has TPM 1.2, Microsoft itself describes a registry entry that enables the upgrade:
- Path:
HKEY_LOCAL_MACHINE\SYSTEM\Setup\MoSetup - New DWORD (32-bit) value:
AllowUpgradesWithUnsupportedTPMOrCPU - Value:
1
After this, the upgrade can be started via the installation media. Important: A TPM must be present; this method only lowers the requirement from 2.0 to 1.2. It does not cover devices without any TPM.
Microsoft clearly states the consequence: Devices that do not meet the requirements are not entitled to updates. In practice, they usually still received them, but it is not guaranteed.
"The registry entry worked straight away - but I knew beforehand that I was relying on goodwill, not a guarantee." A technically savvy private user explains why he consciously only took this route on his private device, not on his company laptop.
The honest calculation
Before you invest time, a sober look at the numbers is worthwhile. A Windows 11 Pro license costs €85.99 from us. A used computer that officially meets the requirements costs between €150 and €300, depending on the equipment.
This results in three sensible approaches:
- Activate TPM in the BIOS, if available. Costs nothing, no disadvantages.
- Registry method for TPM 1.2, if the computer is used privately and you can live with the residual risk.
- Replace hardware, if the computer is used professionally. Working on company devices without guaranteed security updates is difficult to justify with a license price of less than €100.
If the old computer remains in operation for the time being, Windows 10 Pro for €54.99 is the cheapest clean interim solution – with the known caveat that there are no regular security updates for it anymore.
What we do not recommend
Tools circulating online bypass all checks simultaneously. They often work but leave a system whose state you cannot explain to anyone in case of an error. Stick to the documented method or replace the hardware.
You can find the full requirements in the article on Windows 11 System Requirements. All licensing questions are bundled in the Windows Guide, and the Comparison Calculator clarifies which edition suits you.
