Emulator

What are your PC specifications? (including, but not limited to: Operating
System, CPU and GPU)
Im using windows 7 ultimate, I run dolphin in administrator mode.
8GB RAM 64-bit operating system

I think my GCPad just isnt working. My brother helped me in connecting a PS3 Controller and it still doesnt respond.

Are you sure you installed Dolphin 4.0.2 correctly?

Yes I run the installer with administrator rights

Mmm odd, try a dev build then: https://dolphin-emu.org/download/

I tried almost 10 dev build but the result is the same, only wiimote work.
GCPad still doesnt respond in game with either keyboard or ps3 controller.
But in the config it is able to detect for me to set up my controls.
I have checked every time that in config>gamecube that pad 1 to 4 was set to standard controller

I also tried dolphin 3.0, 3.5 and 4.0

It is possible that I'm missing files for GCPad to work? like directx or something? But I have already install directx11

No, i don't think you are missing files, Dolphin doesn't work with plugins anymore or if a file was missing an error code should have appeared.

When you go at the GC pad and you configure a button it light up a red box when you press the key binded at that button?

Just in case check your drivers for updates or check if any has a yellow triangle at the device manager.

Yes the red box light up every time in the GC Pad after setting the controls, also I have check that my drives are all updated

Try using a profile after setting the controls, give it a name ("Keyboard" for example) and then press Save and OK and let's see if it works.

ok maybe I'm a bit late for this topic but I got a answer. Ok so just go wiimote> change NONE to Emulated wiimote> click configure> then device to DInput/0/Keyboard Mouse> on your buttons change it whatever you like, but its better to use your mouse in here A to left click and B to right click and the rest its up to you> next go to Extension change none to Nunchuk then hit configure, in here the buttons are the same but only the left and right click mouse> next to stick section change it to your preferred direction like Up-Down-Left-Right. Don't forget to save it. Hope this work for you. Happy gaming!