It has been fixed now. It seems there was a mistake in letsencrypt
> On 13 February 2018 at 17:49 Aki Tuomi <aki.tu...@dovecot.fi> wrote:
> I'll look into it. Something has failed.
> ---Aki TuomiDovecot oy
> -------- Original message --------From: Marc Weustink <m.weust...@cuperus.nl>
> Date: 13/02/2018 17:44 (GMT+02:00) To: email@example.com Subject:
> Certificate of package repository expired
> I just happened to do an apt update and got a notice that
> repo.dovecot.org was disabled.
> According to firefox:
> repo.dovecot.org uses an invalid security certificate. The certificate
> expired on dinsdag 13 februari 2018 12:48. The current time is dinsdag
> 13 februari 2018 16:39.