Microsoft frequently updates its anti-piracy measures. A script that works today might be blacklisted tomorrow. If the unauthorized KMS server goes offline, your Windows installation will suddenly report that it is not genuine, nagging you with watermarks and limiting personalization features.
During the Windows 10 launch, Microsoft allowed free upgrades. Surprisingly, the activation servers for Windows 8.1 still often accept valid Windows 7 and Windows 8 (non-8.1) keys. windows 8.1 activation txt