gpgsm: certificate is not usable for signing

[Jan Eden]

Hi,

I recently installed GnuPG 2.1 and successfully used gpgsm for about a
week. This morning, signing messages with mutt failed, and the signature
of received messages cannot be verified. Signing a test file reveals:

lbox:~ jan$ gpgsm --verbose --sign testfile.txt
gpgsm: certificate is not usable for signing
gpgsm: certificate is not usable for signing
gpgsm: failed to open '/Users/jan/.gnupg/policies.txt': No such file or directory
gpgsm: Note: non-critical certificate policy not allowed
gpgsm: certificate not found: Ambiguous name
gpgsm: certificate [...]
gpgsm: checking the CRL failed: Not found
gpgsm: validation model used: shell
gpgsm: error creating signature: Not found <GpgSM>

I already tried restoring ~/.gnupg from a backup, without success. It
looks like gpgsm does not find some intermediate certificate.

Thanks in advance for any help.

- Jan