In late October of 2017, Google Chrome released a significant change to the way sites without HTTPS encryption are displayed in the search bar. If your visitor is using incognito mode, or you have any kind of input form on the page, Chrome will display the "Not secure" message:
In order to avoid this, add a SSL security certificate to your website. Check with your webhost about adding one. Depending on your use case, a SSL certificate may be under $20 per year.
For ONTRApages, make sure you use any one of the secure domains we provide in the bottom half of the domain list under SECURE DOMAINS:
ONTRAPORT hosted WordPress sites do not have SSL security certificates available yet (we are working on a solution for those sites). If you are using order forms on those sites we recommend you move the site to a third party host and purchase a SSL certificate.