Here is the warning label you need to read.
Follow the prompts. If the ISO is truly pre-activated, you can skip the "Product Key" field during setup, and the OS will show as "Activated" once you reach the desktop. Conclusion Windows Vista Pre Activated Iso
: Because they are unofficial, you cannot verify the integrity of the installation media. Official ISOs can be verified via SHA-1 hashes to ensure they haven't been tampered with. Actual Good Features of Windows Vista Here is the warning label you need to read
Leo realized then that the "Pre-Activated" dream was a house of cards. He hadn't just downloaded an OS; he'd invited a stranger to live in his kernel. By sunset, he was back on the forums, searching for a copy of Windows XP—this time, from a legitimate disc. Conclusion : Because they are unofficial, you cannot