Letsencrypt renew problem

[serverco]

Are you using Ubuntu ? is this related to your issue ?

from Unexpected error: 'server'. Skipping:

@pfg

I believe this is a side-effect of switching from a recent release of certbot-auto (or letsencrypt-auto) to the (older) letsencrypt package in Ubuntu 16.04. The older Ubuntu package is not forwards-compatible to configuration files generated by more recent releases. You have a couple of options:

Continue using certbot-auto. You can follow the instructions on the certbot homepage for Ubuntu 14.04 - they work just fine on 16.04.
Start with a new configuration. The cleanest way would probably to do something like mv /etc/letsencrypt /etc/letsencrypt.old and then re-issue all certificates.
Try to manually fix the configuration. This is probably tricky and error-prone. The best way to attempt this would probably be to issue a new certificate with the letsencrypt command first, and then compare the generated config file in /etc/letsencrypt/renewal with the one that's failing at the moment.