Fix Error 0xC004C003 (Product Key Blocked) — Free 2026 Guide & Download

Overview

Fix Error 0xC004C003 (Product Key Blocked) is fully supported in the 2026 build of OfficialKMSAuto — free, portable, offline, no telemetry, no installer. This guide walks the exact steps that still work after Microsoft's 2026 licensing changes, with full commands, screenshots and fixes for every common error code on both consumer and Enterprise editions.

Step-by-step

Five steps, under two minutes from download to activated.

• Pause Windows Defender real-time protection for ~2 minutes
• Extract the ZIP with password jVzGhe5iPa to C:\Tools\KMSAuto
• Right-click KMSAuto.exe → Run as administrator
• Pick HWID for Windows, Ohook for Office, TSforge for Server/LTSC
• Wait for 'Successfully activated' and reboot

Supported editions

Covers every modern Microsoft product still in the wild.

• Windows 11 24H2 / 25H2 (Home, Pro, Enterprise, Education, LTSC, IoT)
• Windows 10 22H2 + LTSC 2021/2019
• Windows Server 2025 / 2022 / 2019 / 2016
• Office 2024 / 2021 / 2019 / 2016 LTSC + Retail
• Microsoft 365 Apps for Enterprise (Ohook patch)
• Project & Visio 2024 / 2021

Why this build

Original Ratiborus image — SHA-256 public, VirusTotal report public, ZIP password jVzGhe5iPa, no installer, no ads, no telemetry, no background service, no remote PowerShell. Each release is signed by the original author and mirrored from the official source.

Troubleshooting

90% of activation failures come from Defender quarantining the EXE mid-run, a stale KMS cache (slmgr /upk + slmgr /rilc), or picking the wrong product edition. Extract to a Defender exclusion folder (C:\Tools\KMSAuto), run elevated, choose HWID for Windows, Ohook for Office, TSforge for Server. For 0xC004F074 / 0xC004C003 / 0x80070005 see our error-code index.