Type library exporter encountered generic type Error Meaning

By Etienne Bley
January 23, 2017February 3, 2022

When building my VSTO project I got the following error: ”
Warning Type library exporter warning processing ‘HplAddinAGSL.Agslo.GetFilesToOpen(#0), HplAddinAGSL’. Warning: Type library exporter encountered a generic type instance in a signature. Generic code may not be exported to COM. AGSLo ”

This stems making the VSTO COM visible and the type being using for this function was from systems.collection. In the function with the error I am using List<string> which may not be exported to COM. More research is needed at this point to correct the warning.