Error message "gpg: Can't check signature: Broken public key"

[MFPA]

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What does the error message "gpg: Can't check signature: Broken public
key" mean?

One of the members of PGPNET reports getting that error
message when verifying the signatures on my signed and encrypted
messages to the group. He gets it for the signatures from my EDDSA subkey
0x1712BC461AF778E4, and says he uses GnuGP 2.1.8.


The only references I can find (eg [0]) say:-

  592 GPG_ERR_BROKEN_PUBKEY             Broken public key
  593
  594 The public key was mathematically not correctly generated.



[0]
<http://fossies.org/windows/misc/gnupg-w32-2.1.10_20151204.tar.gz/gnupg-w32-2.1.10/PLAY/src/libgpg-error/doc/errorref.txt>


- --
Best regards

MFPA                  <mailto:2014-667rhzu3dc-lists-groups at riseup.net>

Why is the universe here? Well, where else would it be?
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