The "preactivated" designation indicates that the ISO has been modified to eliminate the need for a retail product key. This carries significant risks:

As of 2026, using a 2021 preactivated build (22000.51) is highly discouraged. Current stable builds (e.g., 25H2 or 26H1) offer significantly better security features, such as enhanced virtualization-based security (VBS) and better compatibility with modern hardware.

There is no way to verify the integrity of the system files, creating potential for unauthorized data access. 2026 Perspective and Alternatives

"Preactivated" ISOs of this nature are not released by Microsoft; they are third-party modified versions (usually via tools like MAS or KMS) designed to bypass license verification. Key Analysis of Windows 11 Build 22000.51

Early reports indicated performance similar to Windows 10, with some users reporting excellent stability while others experienced issues with the new settings menu. Critical Risks of "Preactivated" ISOs

Third-party ISOs may contain bundled malware, spyware, or remote access trojans (RATs) embedded within the activation scripts or system files.

Preactivated systems may fail to receive future Windows cumulative updates or critical security patches from Microsoft, leaving the system vulnerable over time.

As the first insider preview, build 22000.51 was known to be quite stable for an early release, but was not intended for production systems.