windows-iso-downloader

A clean, open-source tool for obtaining official Windows ISO files directly from Microsoft's CDN — without a Windows machine, the Media Creation Tool, or browser restrictions.

Live: msdl.tech-latest.com · By: TechLatest

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What it does

MSDL replicates the session flow that Microsoft uses to serve ISO download links — identical to the approach used by Rufus/Fido. You get the exact same signed CDN URL Microsoft would give you, just without the browser requirement.

• ✅ Direct Microsoft CDN links — no proxying of actual file data
• ✅ 38 languages per release
• ✅ ARM64 + x64 + x86 support
• ✅ No account, no browser lock, no ads, no tracking
• ✅ Links expire in 24 hours (Microsoft's standard behaviour, not a limitation)

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Screenshots

Home	All Releases

Product detail — language selector	Product detail — download links

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Project Structure

windows-iso-downloader/
├── frontend/            # React 19 + TypeScript + Vite + Tailwind v4
├── backend/             # Go proxy server (recommended for production)
├── cloudflare-worker/   # Optional CF Worker for distributed IP routing
└── README.md

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How It Works

Browser → Backend → (CF Worker) → Microsoft API → Signed CDN URL
                          ↓
          1. Register session (Microsoft tracking endpoint)
          2. Parse MDT fingerprint script
          3. Fetch SKU list (available languages)
          4. Fetch signed CDN download URL

The flow mirrors Fido.ps1 by Pete Batard — the same script bundled with Rufus.

Outbound requests to Microsoft are optionally routed through a Cloudflare Worker (cloudflare-worker/worker.js). This distributes requests across Cloudflare's global edge IPs instead of a single server IP, preventing Microsoft's rate-limit block (error 715-123130) under high traffic. The Worker is opt-in via environment variables — omit them to go direct to Microsoft.

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Running Locally

Backend (Go)

cd backend
go run main.go
# Runs on http://localhost:3002

Frontend

cd frontend
npm install
npm run dev
# Runs on http://localhost:5173

Create frontend/.env.local:

VITE_API_URL=http://localhost:3002

Optional: Cloudflare Worker (recommended for production)

Deploy cloudflare-worker/worker.js to Cloudflare Workers, then set these on the backend:

CF_WORKER_URL=https://your-worker.your-name.workers.dev
CF_WORKER_SECRET=your-secret   # must match the CF_WORKER_SECRET secret set in the Worker's settings

Omit both to go direct to Microsoft (fine for local development and low-traffic self-hosting).

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API Reference

GET /skuinfo?product_id=<id>

Returns available languages for a product.

{
  "Skus": [
    {
      "Id": "0x0409",
      "Language": "en-US",
      "LocalizedLanguage": "English (United States)"
    }
  ]
}

GET /proxy?product_id=<id>&sku_id=<sku>

Returns signed download links from Microsoft's CDN.

{
  "ProductDownloadOptions": [
    {
      "Uri": "https://software.download.prss.microsoft.com/...",
      "Architecture": "x64"
    }
  ]
}

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Supported Products

Product	ID	Architecture
Windows 11 25H2	3262	x64
Windows 11 25H2	3265	ARM64
Windows 11 25H2 (updated)	3321	x64
Windows 11 25H2 (updated)	3324	ARM64
Windows 11 24H2	3113	x64
Windows 11 24H2	3131	ARM64
Windows 10 22H2	2618	x64 / x86
Windows 10 22H2 Home China	2378	x64
Windows 8.1	52	x64 / x86
Windows 8.1 Single Language	48	x64 / x86

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Tech Stack

Frontend (frontend/)

Framework	React 19 + TypeScript
Build tool	Vite 8
Styling	Tailwind CSS v4
Animation	Motion (Framer Motion v12)
UI primitives	Radix UI
Toast	Sonner
Font	Geist
Router	React Router v7

Backend (backend/)

Language	Go 1.22+
HTTP	net/http (stdlib, no framework)
Session cache	sync.RWMutex in-memory · 15 min TTL
UUID	github.com/google/uuid
MDT parsing	regexp (stdlib)

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Deployment

Recommended setup:

Component	Platform
Frontend	Cloudflare Pages / Vercel (static)
Backend	VPS (Hetzner, DigitalOcean, Linode, etc.)
Outbound proxy	Cloudflare Worker (optional, recommended for public instances)

⚠️ Deploy the Go backend to a standard VPS, not serverless platforms. The Cloudflare Worker is used only as an outbound proxy for Microsoft API calls — the backend itself must be a long-running process with session state.

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Contributing

Pull requests welcome. To add a new Windows release:

1. Find the product ID on www.microsoft.com/software-download-connector/api/
2. Add it to frontend/public/data/products.json
3. Add related metadata in ProductDetailPage.tsx (PRODUCT_META, RELATED_GROUPS)
4. Update the product table in this README

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Disclaimer

This project is not affiliated with, endorsed by, or sponsored by Microsoft Corporation. Windows is a registered trademark of Microsoft Corporation. All ISO files are served directly from Microsoft's official CDN — this project does not host any files.

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License

MIT © TechLatest