With CloudFlare + SSL, in most cases, you need to head to the Crypto tab and make sure the first drop down box is set to
If that doesn't fix the issue, you'd need to check the your error logs to see if there's an indication of what may be causing the issue(s) you're having.
Generally, for Apache, the error logs are in:
... and for NGINX, they are in:
I'm not 100% sure if that's where Vesta stores the logs as it's been a while since I've used it, but that's the default locations.
You'd want to run
tail on the error logs to pull the last X lines from the logs. For example, if we wanted the last 20 lines of the NGINX error log (and NGINX is installed, of course), we'd run:
tail -20 /var/log/nginx/error.log
From there, you'd take a look at what the error log is showing to be problematic, and work to resolve that issue. Sometimes it's a simple fix, sometimes it's permissions related, sometimes it's more complex. Generally, however, the error log will allow you to diagnose the issue in greater detail.
It's important to keep in mind, a control panel is simply an overlay to what you'd normally need to do from the CLI. It's not a complete replacement for the CLI and you still need to know how to manage, secure, and troubleshoot a web server / server environment, and potentially even OS-level issues.
A control panel can't and won't do these things for you. I say this as a general statement -- it's what I tell pretty much everyone who runs a control panel, whether they're a DigitalOcean customer or not. That doesn't matter to me :-). I like DigitalOcean and I think you would too, but I simply try to help where I can.