The first time I connected my computer Bluetooth keyboard to the Windows Build Samsung Developer Preview tablet I was prompted with a passcode to type into the keyboard:
Entering the passcode followed by ENTER successfully paired the keyboard.
Later on, the pairing quit working so I made attempts to reconnect. Unable to successfully get the two devices to recognize each other again, I Removed the keyboard from the list of Bluetooth devices.
Unfortunately, when attempting to add the keyboard back, I was no longer prompted with the key. Instead, a text box similar to the one below, appeared for me to enter the key:
I tried several keys including “0000” and “1234” but none of them worked.
Eventually I came across this thread and it explained that, when prompted, enter a ‘code’ such as “0000” followed by ENTER (or clicking Next). After that, type the same code (‘0000”) on the keyboard followed by ENTER.
Voilà, problem resolved and the keyboard successfully connects.