Christian Zimmermann writes

CollEc seems to have an invalid or expired certificate, browsers refuse the address.

Christian was supposed to have used the repec wildcard one, which is working. root@helos /etc/letsencrypt/opt/live/repec.org # md5sum cert.pem 02288e353c2cc656ca92a4730693f1d6 cert.pem Source is iripa root@iripa /etc/letsencrypt/live/repec.org # md5sum cert.pem 02288e353c2cc656ca92a4730693f1d6 cert.pem -- Written by Thomas Krichel http://openlib.org/home/krichel on his 21634th day.