If you build Windows Server 2025 or Windows 11 templates and deploy them with guest customization, this one is worth five minutes of your time. It can turn a routine VM deployment into a black screen at login, and it hits Nutanix AHV and VMware vSphere alike. I ran into it after deploying a fresh Windows Server 2025 VM …

If you have ever cloned a Windows VM on Nutanix and watched five identical machines come up with the same hostname, the same SID, and a domain join you have to redo by hand, you already know why guest customization matters. For years my workflow involved hand-rolling an unattend XML file for each new template, version …