VS2008 BIDS package designer not starting and packages do not execute

Hi Folks,

For some reason when I double click on a package or right click and select designer all I get is the xml version of the package - no designer.  If I try to execute a package I get the following:

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Unexpected internal error:  (Microsoft Visual Studio)

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Program Location:

   at Microsoft.DataWarehouse.ProgrammingByContract.Internal.NullCheck(Object obj, String shortMessage)
   at Microsoft.DataWarehouse.ProgrammingByContract.Internal.NullCheck(Object obj)
   at Microsoft.DataTransformationServices.Project.DataTransformationsPackageDebugger.ValidateAndRunDebugger(Int32 flags, DataWarehouseProjectManager manager, IOutputWindow outputWindow, DataTransformationsProjectConfigurationOptions options)
   at Microsoft.DataTransformationServices.Project.DtsPackagesFolderProjectFeature.ExecuteTaskOrPackage(ProjectItem prjItem, String taskPath)

I have gone through days of uninstall/reinstall/restarts of VS2008 and SQL server until I'm now blue in the face.  Any suggestions would be greatly appreciated (short of reformatting the hard drive - not an option)