You can implement XML and XSLT in Sitefinity
in the same way as you implementing it in any ASP.NET Web Site.
As to the error:
Maybe the reason is that the account which is running the aspnet working process (ASPNET or NETWORK SERVICE account) has no permissions for the specified .xml file (C:\Program Files\telerik\Sitefinity3.2\WebSites\productredesign\businesscards-main.xml'
). Please check this out and let us know how it goes.
the Telerik team
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