Hello
Transitioning from WinPE to Windows without a system reboot is a complex process that typically involves boot configuration and system preparation. While Windows Updates can perform this transition seamlessly, it does not provide a direct command or method for end-users to replicate this process manually.
However, there are some advanced methods that might be used in specific scenarios, such as using third-party BIOS tools like CCTK for Dell in WinPE without installing or a reboot, or configuring the Boot Configuration Data (BCD) to boot PE from RAM. These methods are highly technical and may require in-depth knowledge of system boot processes and configurations.
Reboot from winpe back to winpe - Microsoft Q&A
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For a more detailed understanding and step-by-step guidance, you might want to refer to the Microsoft documentation on Windows PE (WinPE), which is a small operating system used to install, deploy, and repair Windows desktop editions, Windows Server, and other Windows operating systems. It's also worth noting that WinRE, which is based on WinPE, can be customized with additional drivers, languages, Windows PE Optional Components, and other troubleshooting and diagnostic tools.