Windows 11 will not do a clean install?

TechWrench

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My current system, running Win 10 Pro, is not Win 11 compatible, so I built a new box with components that are listed as Windows 11 compatible, and I bought a new 11 pro USB from a known vender. It is a stand alone unit at the moment, not hard wired to my router yet. I did a clean Win 10 Pro install first to test the system, and then wiped the drive for the Win 11 install. Once I enter the activation code, I get the notice that the system is not compatible, but no explanation as to why, and no option to go any further. I checked and rechecked the bios settings. TPM is valid and enabled, security setting are enabled. I suspect that not having an active internet connection, might be the problem, but don't know how to verify it. The box does have WiFi capability, so once I get the OS running and can load the Asus drivers CD, I then have a good WiFi connection to my router. I need to keep my present system functional until I can get the new box working, and can move all my stuff over to it. I haven't tried it yet, but am wondering if I create a system boot USB and load the Win 11 compatibility program on it, will that give me an answer?

Any help would be appreciated.
 

Thanks — good detail. Short answer first: an internet connection alone is unlikely to be the root cause — Windows 11 setup will refuse to install if it detects a hardware requirement problem (TPM 2.0, Secure Boot, UEFI/GPT, or unsupported CPU), and that’s usually what the “system is not compatible” message means. You can (and should) try some simple checks that will quickly tell you what Windows Setup is seeing and let you continue the install.
Follow this checklist (step‑by‑step). Do the items in order and report back any messages or the CPU/motherboard model if you want me to check them for you.
1) Try skipping the key during setup
  • When Setup asks for the product key, choose “I don’t have a product key” (or “Skip”) and continue. If Setup will proceed past the compatibility screen without the key, you can install, finish, then connect to the internet and activate Windows 11 Pro later. This is the fastest way to rule out key‑validation being the blocker.
2) Confirm UEFI / Secure Boot / TPM settings in BIOS
  • Windows 11 requires:
    • UEFI boot (not Legacy/CSM)
    • Secure Boot enabled
    • TPM 2.0 (enabled; Intel = PTT, AMD = fTPM)
  • In your Asus BIOS check:
    • Boot Mode / Boot > set to UEFI (disable CSM/Legacy)
    • Security > Trusted Computing or Advanced > confirm TPM Device is present and shows version 2.0
    • Advanced > Intel Platform Trust Technology (PTT) or AMD fTPM set to Enabled
    • Secure Boot > enabled (and make sure you’ve enrolled the Microsoft keys if your BIOS asks)
  • If you’re not sure where these options are in your firmware, tell me the exact motherboard model and I’ll give the menu path.
3) Confirm what the installer sees (no OS required)
  • Boot the PC from the Win11 USB and open the installer’s Repair options:
    • On the first installer screen press Shift+F10 to open a Command Prompt.
    • Run: wmic path win32_computersystem get SystemType (to see if firmware is UEFI/GPT) — note: this may return limited info from WinPE.
    • Better: reboot into BIOS and confirm the settings above visually (TPM version, Secure Boot state, Boot mode).
  • If you can boot a temporary Windows 10 installation (you said you installed Win10 earlier to test), run these inside Windows:
    • Run msinfo32 → System Summary: check “BIOS Mode” (should be UEFI) and “Secure Boot State” (should be On).
    • Run tpm.msc → look for “Specification Version” = 2.0.
4) Recreate the USB installer the Microsoft way
  • Some vendor-supplied USB sticks are fine, but to eliminate media issues recreate the USB with Microsoft’s Media Creation Tool (or use Rufus and select GPT for UEFI and Windows 11).
  • If Rufus, pick the Windows 11 ISO, Partition scheme = GPT, Target system = UEFI (non-CSM).
  • Boot the PC to the USB using the UEFI boot option in your motherboard boot menu.
5) CPU compatibility
  • Even if the board lists Windows 11 compatible, the exact CPU model matters (Microsoft maintains a supported CPU list). If BIOS/TPM/Secure Boot are correct and you still get “incompatible”, post the CPU model and I’ll check the supported list for you.
  • You can get the CPU name from the BIOS or from the motherboard box/manual.
6) BIOS/firmware update
  • If everything above looks correct, update the motherboard BIOS to the latest stable firmware (Asus site). Many compatibility problems are fixed in firmware updates. Follow Asus instructions exactly; make a backup of settings first.
7) TPM clearing — only if necessary
  • If TPM shows but Windows setup still complains and you’ve verified the BIOS options and bios is updated, one troubleshooting step is to clear the TPM in BIOS and then boot (this sometimes resets any bad state). DO NOT clear TPM if you have BitLocker or other keys on the drive you need — clearing will permanently destroy keys. Only do this on a drive with no data or where you’ve backed up keys.
8) If you want to run a compatibility tool
  • Microsoft’s PC Health Check (or third‑party WhyNotWin11) will give an explicit reason (TPM not present, Secure Boot off, CPU not supported, etc.). Best place to run them is from a working Windows install (your temporary Win10 test install), or run them on another working PC. They are not normally run from the raw WinPE environment unless you build a WinPE with the tool included.
  • So: reinstall Win10 temporarily (or keep your test Win10 install) and run PC Health Check — it will give the exact failing requirement. That is the most direct way to get an explicit explanation.
9) Quick troubleshooting summary:
  • Skip product key first (fastest test).
  • Confirm UEFI boot, Secure Boot On, TPM 2.0 enabled in BIOS.
  • Recreate USB with Microsoft Media Creation Tool (GPT/UEFI).
  • Update BIOS.
  • If still blocked, provide CPU + motherboard model and the exact installer message (or a photo) and I’ll check the cause.
What I need from you if the steps above don’t fix it
  • Exact CPU model and motherboard model (eg “Intel i7-12700K” and “Asus ROG Strix Z690-E”).
  • Screenshot or exact wording of the “system is not compatible” message.
  • Whether you were booting the USB in UEFI mode (how the boot option showed in the Boot menu — “UEFI: <USB name>” vs “USB: <name>”).
If you want, start by trying step 1 (skip the key) and recreating the USB with Media Creation Tool. Tell me the result and the CPU/motherboard if it still refuses to install — I’ll take it from there.
 

Thanks, I will work my way thru your suggestions and report back.
 

Sounds good — thanks for taking a methodical approach, Gary. A few quick reminders and tiny bits of extra help as you work through the list:
  • Fastest first: try skipping the product key on the installer (“I don’t have a product key”) and continue. That often rules out key/activation being the blocker.
  • While in your temporary Win10 install (or after you boot WinPE from the USB), these checks tell you exactly what Windows sees:
    • Run msinfo32 → look at “BIOS Mode” (should be UEFI) and “Secure Boot State” (should be On).
    • Run tpm.msc → check “Specification Version” (should show 2.0).
    • Or from an elevated PowerShell run: Get‑Tpm (shows TpmPresent, TpmReady, SpecVersion).
  • When recreating the USB:
    • Prefer Microsoft Media Creation Tool or Rufus with Partition scheme = GPT and Target = UEFI (non‑CSM).
    • Boot the USB via the UEFI entry in your boot menu (it will show as “UEFI: <USB name>”).
  • Don’t clear the TPM unless you’re sure there are no keys (BitLocker) to lose.
  • If you still hit the compatibility block, please share:
    • Exact CPU model and exact motherboard model.
    • The exact installer message (a photo is fine).
    • How the USB boot option appears in the boot menu (“UEFI: …” vs “USB: …”).
When you’ve tried the steps, post the results and any error text/screens, and I’ll walk you through the next actions (BIOS menu paths, BIOS update steps, or checking CPU support lists). Good luck — I’ll be here to help.
 

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