Website visitors report SSL errors when trying to visit my Ghost site? Help!

My target audience here is site owners who are getting an occasional report of SSL errors from their website visitors. If everyone is seeing an error, you probably want to escalate to your host (if in paid hosting), or come on over to the forum for some help, if self-hosting.

I can't access your site at work! ERR_SSL_PROTOCOL_ERROR, etc...

If you're lucky 🍀, you'll get a fairly technical user reporting a problem like this, with enough interest to swap multiple emails, who may be able to provide enough info to get it resolved.

Questions that might help with diagnosis:

• Is it a problem in multiple browsers?  If it works on some browsers, that suggests that it's something in that browser's configuration (ad blocker, antivirus software, etc?), and it's also an immediate workaround for this user.
• If there's a VPN, try turning it off.
• If the problem occurs on a laptop or phone:  Does the problem still exist on another network?  (Take the phone off WiFi, or try on the laptop at home.)  If the problem disappears on a different network, that suggests network blocking rather than a device configuration problem.  See suggestions under "multiple devices"
• Is it a problem on multiple devices on the same network?  (Can a colleague also not access the site?)  Multiple devices suggest that site security is blocking it, and asking the business' IT person to unblock it or identify what security software they're using (so that you can ask Ghost support to follow up with the software vendor) is a good next step.

Ask for screenshots of the error message. Ask for browser (including version) and operating system (including version).

Other things to try, if it's a one-device problem (not a network-wide problem):

• Is the system time set correctly?
• Is the browser up to date?  Is the operating system up to date? 
• Clear browser cache and cookies:
  • Google Chrome: Settings > Privacy and Security > Clear browsing data
  • Mozilla Firefox: Options > Privacy & Security > Cookies and Site Data > Clear Data
  • Safari: Safari > Clear History and Website Data
  • Microsoft Edge: Settings > Privacy > Clear browsing data
• Windows only: Clear SSL State
  • Press Windows + R to open the Run dialog.
  • Type inetcpl.cpl and press Enter.
  • In the Internet Properties window, navigate to the Content tab.
  • Click Clear SSL state.

New domain?

Many institutional/corporate firewalls block newly-registered domains, as potential phishing/malware sources. I've generally seen this only within a site's first week of registration. This is a good argument for registering your domain a month or so before you intend to use it. Don't make registering your domain the last thing you do before launch.

Newly moved domain?

Sometimes your previous hosting setup may have left users with a cached SSL certificate. [They can try the reset options below.] This is a good reason to not move your domain from your previous host to Ghost as the last moment. Consider a "soft launch" where you move your DNS one day, and announce it the next.