FAQ (Frequently Asked Questions)
Why do my visitors get a warning saying my guestbook is not secure?
Since late 2017 some browsers (including Google Chrome) have started showing security warning on all website loaded via HTTP that has an input field on it (which your guestbook has).
You can fix this by switching over to HTTPS (SSL) but you will need to upgrade to a premium account first. Then just change http:// into https:// in your guestbook link from your website.
If you already are a premium user and embedding the guestbook with an iframe onto your site, then you have to contact your hosting provider so they also upgrade your entire website to HTTPS. This is not necessary if you are just linking your guestbook from your website, which most users are.