From
Mart Muller:
When implementing SharePoint Portal Server, there are cases that you have to create the same portal structure a few times. For example, all the developers need to have the same portal on their development machine, there is a test enviroment or a production enviroment. Then when the portal goes live, you’ll have to create an empy portal again with the same stucture and content as the test enviroment. SPS provides config files that can help you with this in a very efficient way: SPSPredefinedCategories.xml.
The SPSPredefinedCategories.xml file is located in the SPS site template directory (Program Files\Common Files\Microsoft Shared\web server extensions\60\TEMPLATE\1033\SPS\SPSConfig\) and it contains the complete structure of a clean portal. So, when you create a new portal, it contains the news area, the sites area and a topic stucture etc..
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