Unable to export code from schema (.xsd file) using the xsd.exe in visual studio 2010 Beta

I have a .xsd file created on .NET Framework 2.0

Now Iam trying to export code  from this .xsd file using the xsd.exe  on .NET Framework 4.0 ( I have Visual Studio 2010 Professional beta installed on my machine)

When given the command " xsd /c"  in the visual studio command prompt  i get an error
"Error generating classes for schema    
     -A required privilege is not held by the client "