Which keyboard are you trying to use to enter the PIN?

I have the same problem.  I can connect the mouse fine but it wants a passkey which is not listed anywhere in the documentation that came with the keyboard/mouse combo.  By the way, I'm trying to key in a code using the wireless keyboard to sync it to the laptop but it only recognizes the built-in keyboard.

The key is one you make up yourself in order to securely pair the device to your system. Use the internal KB to enter the code for the Bluetooth on the system then once that is done you will enter the key using the Bluetooth keyboard. If you have a mouse you may need to do that device first and use the internal KB to enter the code for the mouse and for the system.