Hello,
Modern security likes to white list COM addin progids or Guids. However for ExcelDNA task panes there seems to be an internal wrapper and no way to specifie these.
I tried the following, but they seem internal.
using (new SingletonClassFactoryRegistration(userControl, clsId))
using (new ProgIdRegistration(progId, clsId))
using (new ClsIdRegistration(clsId, progId)) {
CustomTaskPaneFactory.CreateCustomTaskPane(progId, "Formulas and Bookmarks");
Any thoughts? (Annotations work fine for ordinary COM root.)