VSTO problem - cannot create visual studio excel workbook project

Question

When I try to create a Excel 2007 Workbook project, in Visual Studio 2008, I get the following errormessage:

Project cannot be created because the \"Excel

Answer 1

I'd set Excel 2003 to open XLS files by default. I saw the same error message you got until I repaired Office 2007 from the Add/Remove Programs menu.