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Windows 11 26H2 · build 26300.9457

Stop following out-of-date tutorials.

Plenty of Windows guides online were written for builds long gone. Every page here shows the date it was checked and the build it applies to.

215 pages18 reproduced in the labupdated 2026-10-29

Recently verified

Pages checked again most recently. E2 was reproduced in the lab; E1 follows the official documentation.

Virtualisation flags: checking VT-x, IOMMU, SLAT and nested supportBuild 26300.9457E2Proxmox host memory: what Windows guests really costBuild 26300.9457E2The lab: how a page earns its evidence badgeBuild 26300.9457E2Windows Admin Center: install, secure and actually use the gatewayBuild 26300.9457E2Windows downloads: the official sources, verifiedBuild 26100.33650E1Lab downloads: Proxmox VE, VirtIO drivers, Rufus, VentoyBuild 26100.33650E1

Start with the task

What are you trying to do?

Pick the job, not the chapter. Each path starts with the decision and ends with a way to verify it.

Task

Install Windows cleanly

Official 26H2 media, UEFI, TPM 2.0 and the installer’s own partition layout.

→Checklist

Set up a new PC

Updates, drivers, browser, privacy and backup — the first ten minutes that matter.

→Setup

Develop on Windows

WSL2 and Ubuntu on a D: Dev Drive, with the ReFS limits stated up front.

→Method

Measure a game

Frame time and 1% low before any tweak; a ledger for every change.

→Troubleshoot

Fix a DLL error

Identify the missing runtime, check bitness, repair the store — never download a random DLL.

→Admin

Run Windows Server

Editions, licensing, PVE installs and the minimum roles for a rebuildable homelab.

→

If you are new

Four steps to a PC you can trust

Do not start with a tweak. Start with the build, the install and the first boot.

  1. 01

    Choose the build

    26H2, 25H2, LTSC or Arm: pick for support and hardware, not a benchmark screenshot.

    Compare versions →
  2. 02

    Install it clean

    Official media, UEFI, TPM 2.0 and a partition layout you can explain.

    Clean install guide →
  3. 03

    Finish the first hour

    Drivers, updates, RDP, encryption and a backup before installing a toolchain.

    First 10 minutes →
  4. 04

    Go deeper by task

    Develop, measure, troubleshoot or move to Windows Server.

    Browse Windows →

Inside the lab

Screenshots, not stock photos.

Every E2 page starts from a reproduced VM. These are the actual captures behind the guides.

msinfo32 on Windows 11 Pro 26H2 showing build 26300, UEFI and Secure Boot On.
E2 · Clean install

Windows 11 Pro 26H2, build 26300.9457

UEFI, Secure Boot On and TPM 2.0 ready — verified in the guest, not assumed from the VM config.

PowerShell showing D: as a ReFS Dev Drive, WSL 3.0.3 and Ubuntu 24.04 with its VHDX on D:.
E2 · Developer setup

WSL2 + Ubuntu on a D: Dev Drive

WSL 3.0.3, Ubuntu 24.04 and the ext4 VHDX on D: — with the ReFS performance caveat stated, not hidden.

Windows Security Core isolation page showing Memory integrity On.
E2 · Measured

Memory integrity: on, off, measured

Three runs per state. The CPU/memory delta was inside the noise; the page says exactly that.

Browse the library

Eight ways in

No endless sidebar. Choose a category, then a page that matches the job.

01Start hereVersions, install, first boot02Install & upgradeMedia, UEFI, TPM, partitions03DevelopWSL2, Dev Drive, toolchains04Gaming & performanceFrame time, 1% low, HVCI05TroubleshootDLL, runtime, 0xc000007b06Windows on ArmPrism, drivers, 26H1/26H207Windows ServerEditions, licensing, roles08HardwareNVIDIA, AMD, Intel, Hygon09DownloadsOfficial ISOs, verified
01

Build-specific

Every page names the Windows build and edition it applies to. 26H2 means 26300, not “Windows 11”.

02

Evidence first

E1 is documentation, E2 is a reproduced lab, E3 is physical hardware. We do not blur the three.

03

Rollback included

A snapshot, a restore point or a reverse command. If a page cannot offer a way back, it says so.

WinBook is independent documentation. Not affiliated with Microsoft. No ISO mirrors, activation tools or DLL downloads.