Iterating Projects in Solution with Solution folders

Hi,

I am trying to use the code in following URL to iterate projects inside a solution which has solution folders.

http://www.wwwlicious.com/2011/03/envdte-getting-all-projects.html#!/2011/03/envdte-getting-all-projects.html

However I get compile time errors in line

if (subProject.Kind == ProjectKinds.vsProjectKindSolutionFolder)

The error is 'EnvDTE80.ProjectKinds' does not contain a definition for 'vsProjectKindSolutionFolder'.

However Intellisense on ProjectKinds shows 'vsProjectKindSolutionFolder'. What could be the issue here?

Thanks.

Ajeeth Kumar.A, Cognizant