SSL Certificate Errors-browser warnings and fixes

SSL certificate errors appear when browsers detect a problem with your HTTPS connection - expired cert, domain mismatch, untrusted issuer, or mixed content (secure page loading insecure resources).

Certificate is untrusted

Error: "Your connection is not private" or "Certificate not trusted"

• Cause: Certificate signed by unrecognized authority (self-signed or invalid CA)
• Fix: Install proper certificate from Let's Encrypt or your CA
• UnderHost provides free AutoSSL (Let's Encrypt) - should auto-install
• If missing, go to cPanel → AutoSSL and enable

Certificate expired

Error: "Certificate expired" in browser

• Cause: Certificate validity period ended (typically 1 year)
• Fix: Renew certificate
• AutoSSL auto-renews 30 days before expiry
• If using paid certificate, renew through your CA before expiry

Domain mismatch error

Error: "Certificate doesn't match this website"

• Cause: Certificate is for different domain (e.g., cert for example.com but visiting www.example.com)
• Fix: Request certificate for correct domain or use wildcard certificate (*.example.com)
• Check your domain matches certificate exactly

Mixed content warnings

Error: "Mixed Content: The page at 'https://...' was loaded over HTTPS, but requested an insecure resource 'http://...'"

• Cause: HTTPS page loading image/script over HTTP
• Fix: Change all URLs to HTTPS (in wp-config.php, theme, plugins)
• WordPress: Settings → General → ensure both URLs start with https://

How to fix SSL issues

Check certificate status

Use UnderHost SSL Check tool

For UnderHost shared hosting

1. Go to cPanel → AutoSSL
2. Click "Issue" or "Renew" for your domain
3. Wait 5 minutes for issuance
4. Clear browser cache and reload

Force HTTPS redirect

Add to .htaccess:

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

Related: AutoSSL setup | Advanced SSL

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