EinsKatze:
Hi everyone, this basically is a guest-post. This guide is entirely written by TimLew, shoutout to him! 💖 His Discord Username: timlew

Step 1: Download the ISO File

Download Link: https://drive.massgrave.dev/de-de_windows_10_enterprise_ltsc_2021_x64_dvd_71796d33.iso

Note: This is the standard Windows 10 Enterprise LTSC ISO (non-IoT), but it retains your system language as German.

Step 2: Verify System Language

  1. Open PowerShell as Administrator.
  2. Run:
dism /english /online /get-intl | find /i "Default system UI language"

If the output shows German (de-DE), proceed.

If not, download the correct language ISO from: Windows LTSC Versions

Step 3: Backup Your Data

⚠️ Backup all critical files from your C: drive (bookmarks, passwords, photos, etc.).

Note: While the upgrade process is generally stable, you may technically “downgrade” from 22H2 to 21H2. Proceed with caution.

Step 4: Modify the Registry Key

In PowerShell (Admin), run:

reg add "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion" /v EditionID /d IoTEnterpriseS /f

Immediately mount the ISO and launch setup.exe.

Step 5: Perform the Upgrade

During setup, select “Keep personal files and apps”.

⚠️ Act quickly – this option may disappear if you are not fast enough!

Allow the installation to complete.

Step 6: Activate IoT Enterprise LTSC

Use the following Windows activation key after the upgrade: QPM6N-7J2WJ-P88HH-P3YRH-YY74H

Your system may restart automatically or request to do so.

Step 7: Legitimate Activation

Open PowerShell (Admin) and run:

irm https://get.activated.win | iex

Select Option [1] (or 3/4/5). Option [1] is preferred.

Step 8: Restore Microsoft Store (if needed)

Run in PowerShell (Admin):

wsreset -i

Wait 2 minutes for the Store to reinstall. There my be Warnings, ignore them.

Download AppInstaller (if needed): https://apps.microsoft.com/detail/9nblggh4nns1.

The Microsoft Store must be installed for this step.

✅ Done! Your system is now running Windows 10 IoT Enterprise LTSC.