Hello @MahmoudJo-2131
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Thank you for your patience and for elaborating on your concern.
Root Cause
This activation issue typically arises because Windows Enterprise activation after Autopilot/Entra Join is subscription‑based, not tied to the Pro product key you purchased. After a reset and re‑enrollment, Windows may attempt to reuse the Pro key, which then fails with “already in use.” The correct activation path is via your organization’s Microsoft 365 E3/E5 or Windows E3/E5 entitlement.
Troubleshooting Steps
1. Verify Licensing Entitlement
Ensure the user/device has a Windows Enterprise license (E3/E5, Microsoft 365 E3/E5).
Check in Microsoft Entra admin center → Licenses → confirm Windows Enterprise is assigned.
2. Check Activation Status
Go to Settings → Update & Security → Activation.
If it shows “Windows is not activated” with a product key error, it’s still bound to the Pro key.
If it shows “Windows is activated with a digital license linked to your organization”, Enterprise is active.
3. Force Subscription Activation
Run: slmgr /upk to uninstall the current product key.
Run: slmgr /rearm to reset activation state.
Reboot the device.
Windows should re‑activate automatically via Entra/Intune subscription.
4. Confirm Autopilot Profile Settings
In Intune → Devices → Windows enrollment → Deployment profiles, ensure the profile is set to upgrade to Enterprise.
If misconfigured, the device may fall back to Pro key activation.
5. Escalate if Needed
If activation still fails, open a Microsoft Support case.
Provide the device’s hardware ID and licensing assignment so Microsoft can clear the activation mismatch.
I hope this clarifies why the Pro key becomes invalid after reset and how to restore proper Enterprise activation.
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