Unactivated Windows 8.1 will run indefinitely with minor limitations:
Microsoft’s official free upgrade offer for Windows 7/8.1 ended years ago, but many users report the upgrade still works using the Media Creation Tool and entering a Windows 8.1 key during installation. This results in a digitally licensed Windows 10/11 installation. windows 81 activation kmspico v913 final download verified
Tools claiming to activate Windows or Office without a valid license, often referred to as "activators" or "KMS emulators," pose significant security and legal risks. Unactivated Windows 8