Using unofficial activation tools like KB780190 carries significant risks:

For the loader to function, Windows 7 had to be installed with the standard 100MB system reserved partition .

Today, developers needing to test environments on older operating systems typically use more secure, legitimate methods:

It was designed to remain active even after Microsoft released KB971033 , an official update for "Windows Activation Technologies" (WAT) meant to detect such exploits. Risks and Security Considerations

Modifying the bootloader can lead to boot failures, especially during subsequent official Windows updates.

It aimed to permanently activate Windows 7 Professional and Ultimate editions for both 32-bit (x86) and 64-bit (x64) architectures.