This article contains information about custom site definitions in Microsoft Windows SharePoint Services 2.0,Windows SharePoint Services 3.0, and SharePoint Foundation 2010. It also contains information about custom area definitions in Microsoft Office SharePoint Portal Server 2003,Microsoft Office SharePoint Server 2007 and SharePoint Server 2010. This article lists scenarios that are supported and scenarios that are not supported when you customize site definitions and area definitions.

Supported scenarios

When you work with custom site definitions or custom area definitions, the following scenarios are supported:

• To create a custom site definition or a custom area definition, you copy an existing site definition or an existing area definition, and then you rename and modify the new site definition or the new area definition. For more information about this supported method, visit the following Microsoft Web site:
  http://msdn2.microsoft.com/en-us/library/ms868598.aspx (http://msdn2.microsoft.com/en-us/library/ms868598.aspx)
• You modify the .xml files and the .aspx files in a custom site definition or in a custom area definition before you create new sites or new portal areas by using the custom site definition or the custom area definition.
• You deploy the custom site definition or the custom area definition. That is, you create new sites or new portal areas by using the custom site definition or the custom area definition. To modify the new sites or the new portal areas that you created, you use one or more of the following three supported methods:
  • You modify the site or the portal area by using Microsoft Office FrontPage 2003, SharePoint Designer 2007, or SharePoint Designer 2010.
  • You programmatically modify the site or the portal area by using the SharePoint Portal Server object model or the Windows SharePoint Services object model.
  • You modify the site or the portal area by using Microsoft Office FrontPage 2003.
  Note These three methods are also supported methods to use if you want to modify the Default.aspx page in the portal site. Microsoft does not support using other methods to modify the Default.aspx page in the portal site.

Unsupported scenarios

When you work with custom site definitions or custom area definitions, the following scenarios are not supported:

• You modify one of the default site definitions or one of the default area definitions that are included in SharePoint.
  
  We do not support modifying the default set of site definitions or area definitions that are installed when you install SharePoint. Additionally, we do not support modifying the .xml files or the .aspx files in the default site definition or in the default area definition.
• You modify a custom site definition or a custom area definition after you deploy the custom site definition or the custom area definition.
  
  We do not support modifying a custom site definition or a custom area definition after you create a new site or a new portal area by using that site definition or area definition. Additionally, we do not support modifying the .xml files or the .aspx files in the custom site definition or in the custom area definition after you deploy the custom site definition or the custom area definition.
• You modify the Webtemp.xml file or the Webtempsps.xml file that is located in the following folder:
  Drive:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\60\Template\LCID\XML
  
  or
  
  Drive:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\Template\LCID\XML
  
  or
  
  Drive:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\Template\LCID\XML
• We do not support modifying files that reside in the _layouts folder. We reserve the right to update these files in software updates or service packs at a later date. This may cause the custom changes to be lost. You must always back up files that you have changed so that you can restore them at a later date.

For more information about the best practices for ensuring application reusability and upgrade in SharePoint, visit the following Microsoft Web site: For more information about templates and site definitions, visit the following Microsoft Web sites:

• http://msdn2.microsoft.com/en-us/library/ms980852.aspx (http://msdn2.microsoft.com/en-us/library/ms980852.aspx)
• http://msdn2.microsoft.com/en-us/library/ms980845.aspx (http://msdn2.microsoft.com/en-us/library/ms980845.aspx)

For more information about schema files in site definitions, visit the following Microsoft Web site: For more information about custom templates, click the following article number to view the article in the Microsoft Knowledge Base: For migration and upgrade information for SharePoint Server 2007 developers, visit the following Microsoft Web site:For more information about the SharePoint Portal Server object model and the Windows SharePoint Services object model, see the Microsoft SharePoint Products and Technologies Software Development Kits (SDKs). To view the SharePoint Products and Technologies 2003 SDK, visit the following Microsoft Web site: To view the SharePoint Products and Technologies 2007 SDK, visit the following Microsoft Web site: