I had the same Problem with a new Magento 2.1.7 installation, php 7.0.2, mysql 5.6. in developer mode and the cronjob always send me an email with: Class 'IntlDateFormatter' not found in /vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 93
My solution was:
Both entries for the base-urls (secure und unsecure) under "stores > configuration > general > web" had to be the secure (https://) domain.
Now everything works fine.