I'm busy using the Word-inerop interface to search a Word document, but get an Error when trying to search for all bold text.

The code looks like this:
Microsoft.Offic e.Interop.Word. ApplicationClas s vk_word_app = new Microsoft.Offic e.Interop.Word. ApplicationClas s();

object vk_read_only = false;
object vk_visible = true;
object vk_false = false;...