If this is the 1st pairing of the 2 devices you enter the passkey in windows where it is asking and the phone will ask for the key and you enter the same key and they are then paired.
If you have a Nokia phone when paring with your computer the computer will ask you for a passkey you type it in and then the phone will ask you for the same passkey.
If you are paring a headset try reading through the manual, because more than likley there is a default passkey entered into the hardware of the headset.
I have that card from a dead T41p and transplanted into my A30p (or else for other machines I have 1803 error is no go). Now after using the Windows...
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