Following the answer in this thread -Linking and showing archive by month by P&T has worked fine for previous sites but now I'm getting the following error. I've checked I have a Time zone selected in System settings.
DateTime::modify(): Failed to parse time string (first day of archive
2018 00:00:00) at position 13 (a): The timezone could not be found in
the database
Template:
{% set month = craft.request.segment(3) %}
{% set year = craft.request.segment(4) %}
{% set firstDay = now | date_modify('first day of ' ~ month ~ ' ' ~ year ~ ' 00:00:00') %}
{% set lastDay = now | date_modify('last day of ' ~ month ~ ' ' ~ year ~ ' 23:59:59') %}
{% set archive = craft.entries.section('bulletinOnline').postDate('and', '>= ' ~ firstDay, '<= ' ~ lastDay) %}
{% for entry in archive %}
...
{% endfor %}
