How to Fix SSL Errors in Chrome/Firefox/Safari
To fix browser SSL errors: (1) check the certificate via SSL checker — see the exact cause; (2) reissue via certbot/Let's Encrypt; (3) configure fullchain + TLS 1.2/1.3 on the server; (4) recheck + clear the browser SSL cache.
Step-by-step guide
- Identify the error type. Chrome: NET::ERR_CERT_AUTHORITY_INVALID = untrusted CA. ERR_CERT_DATE_INVALID = expired. ERR_CERT_COMMON_NAME_INVALID = wrong domain. ERR_SSL_PROTOCOL_ERROR = TLS incompatibility.
- Diagnose with the SSL checker. Open /en/ssl, enter the domain. Get the full certificate chain, expiry, issuer, grade.
- Reissue the certificate. For Let's Encrypt:
certbot --nginx -d example.com. For a commercial CA — via the registrar's panel. - Configure fullchain. nginx:
ssl_certificate /path/fullchain.pem;(not just cert.pem). Apache:SSLCertificateFile+SSLCertificateChainFile. - Update TLS versions. Enable TLS 1.2 and 1.3, disable 1.0/1.1 (deprecated in Chrome 90+).
- Recheck. Return to the SSL checker — the grade should be A or A+.
- Set up monitoring. Enable SSL monitoring — get a 14-day expiry alert ahead of time.
Why teams trust us
How it works
Enter domain
TLS chain verified
Expiry date & vulnerabilities
What Does the SSL Check Cover?
SSL/TLS is the encryption protocol that protects data between the browser and server. Our tool analyzes the certificate, chain of trust, TLS version, and knownvulnerabilities.
Certificate Details
Issuer, validity period, signature algorithm, covered domains (SAN), and validation type (DV/OV/EV).
Chain of Trust
Full chain verification: from leaf certificate through intermediates to root CA.
TLS Analysis
Protocol version (TLS 1.2/1.3), cipher suites, Perfect Forward Secrecy (PFS) support.
Expiry Alerts
Set up a monitor — get Telegram and email alerts 30/14/7 days before expiration.
DV vs OV vs EV Certificates
- Confirms domain ownership only
- Issued in minutes automatically
- Free via Let's Encrypt
- Suitable for most websites
- Most common certificate type
- Organization (OV) or Extended Validation (EV)
- Issued in 1-5 business days
- Costs $50 to $500/year
- For finance, e-commerce, government sites
- Increases user trust
Who uses this
DevOps
SSL certificate monitoring
Security
TLS config audit
SEO
HTTPS as ranking factor
E-commerce
customer trust
Common Mistakes
www and subdomains.Best Practices
Strict-Transport-Security header forces browsers to always use HTTPS.Get more with a free account
SSL certificate monitoring, check history and alerts 30 days before expiry.
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How-to
Frequently Asked Questions
Is signup required?
For a quick check (1-2 requests/min) — no. For continuous monitoring — free account. No credit card.
Is this free?
Yes. Enterno.io Scout is a forever-free plan with 5 monitors. All basic tools without signup.