I recently came across an issue while deploying Windows Server 2012 from a template using the VMware customization wizard in ESXi 5.1. The VMware customization wizard allows you to deploy your template with custom attributes, such as computer name, product key, etc. and then syspreps the system. With my new Windows Server 2012 template, the customization wizard appears to not run after first boot as intended. After some research, I came across a VMware article that indicates this is a known issue with VMware 5.1 and earlier. To resolve this issue, you must manually reboot your virtual machine one time after its initial boot. After the second boot, the customization wizard starts and syspreps the machine. Fully patched environments running on 5.1 reportedly do not have this issue.
As always, if you have questions you can contact the PEI Operations team for all of your support needs at 303-786-7474 x1 or firstname.lastname@example.org
Andy Shaffer, PEI