Hi 12ddl4u,
Have you installed the latest updates for Revit 2013? I have listed the link below to download:
http://revitclinic.typepad.com/my_weblog/2013/06/update-release-3-for-the-revit-2013-products.html
Please check if you install .NET Framework 4.5 in the control panel. For Revit 2013 is using .NET Framework 4.0. Maybe issue with .net 4.5:
Additional suggestions:
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