Quoting Jaap Winius <jwinius@???>:
> My first attempt to configure DKIM on a Debian wheezy box running
> Exim4 4.80 (exim4-daemon-heavy) keeps ending with this error:
>
> DKIM: signing failed (RC -102)
Solved this one myself. All I really did was to use a 2048-bit key
instead of the 256-bit key that I had created earlier and the error
disappeared. The full set of commands that I used to generate both the
private and public keys was: