Hi. I can't get Dolphin 2745 to recognize the VideoDX9 Plugin, and I had to download dolphin several times because the download kept stopping in the middle. I finally got it all downloaded completely, but the plugin issue is real. It is in the plugin folder, but dolphin only shows the opengl plugin. I can take another dx9 plugin from an older emulator, and dolphin recognizes it then. What's happening?
You need to update your DirectX to the latest version. (Even if you're already at "9.0c" you still need to grab the latest update to that, yeah it's weird I know.) Run the DirectX updater from the Microsoft Website, and Dolphin should then be able to load the newer DirectX graphics and input plugins.
Be warned however: The DirectX graphics plugin is under very very heavy maintinance right now and isn't working at all, so you should still use OpenGL graphics. You *do* need to do this for any of the input plugins to load though. ^_^
-gamefreak