For guest OS cutomization to work when deploying from a template, the vCenter server needs to have the sysprep files for that operating system to be able to customize its settings.

If you do not you will get the following error when deploying from a template:

Warning: Windows customization resources were not found on the server

Use the download links below to get the sysprep files from Microsoft and extract the contents to the correct folder within

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep

Sysprep 1.1 Download

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\1.1

Copy contents of the "tools" folder to the "1.1".

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\2k

Copy contents of i386\deploy.cab to "2k".

Windows 2003 SP2 Download

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\svr2003

Copy contents of system32\deploy.cab to "svr2003".

Windows 2003 SP2 x64 Download

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\svr2003-64

Copy contents of SP2QFE\deploy.cab to "svr2003-64".

Windows XP SP3 Download

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\xp

Copy contents of CAB file to "xp".

Windows XP SP3 x64 Download

C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\sysprep\xp-64

Copy contents of SP2QFE\deploy.cab to "xp-64".

Note: Windows Server 2008, Windows Server 2008 R2, Windows Vista and Windows 7 use a new method for imaging which does not require sysprep files on the vCenter server.