I am trying to follow the "Getting Started with Excel-DNA" procedure and every time I open the Test1.xll file I get an error "File format and extension don't match". I have the option to proceed; however, when I do the worksheet just
populates with random characters. I have attached a screenshot to show what is happening.
I am using Excel 2013 with Windows 7. I have the .NET 3.5.1 runtime installed and I have macro security set as low as it will go.