It is possible for an OEM system builder to customize the Welcome Center, so it also includes special links to products and features added by the OEM system builder. More Info Walkthrough: Customize Welcome Center.
If wanting to modify the Welcome Center after Windows Vista has been installed, then it can be done by editing Oobe.xml. The <useroobe> xml-node contains the Welcome Center modifications.
The location of the Oobe.xml can be one of the following places:
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