ERR_BAD_SSL_CLIENT_AUTH_CERT
ERR_BAD_SSL_CLIENT_AUTH_CERT Error
What This Error Means
This error occurs when the server requires a client certificate for authentication (mutual TLS), but the certificate provided by the browser is invalid, expired, or revoked.
Common Causes
- The client certificate installed on your device has expired.
- The certificate is corrupted.
- You selected the wrong certificate when prompted.
- The server does not trust the issuer of your client certificate.
How to Fix It (For Users)
- 1 Obtain a new valid client certificate from the administrator.
- 2 Remove old/expired certificates from your OS certificate store.
- 3 Clear SSL state in browser and restart.
For Site Owners / Developers
- Ensure your server is configured to trust the CA issuing client certs.
- Check if the CRL (Certificate Revocation List) is accessible.
- Verify the client certificate chain.
When It Is NOT Your Fault
If the server's trust store is misconfigured.
Check if this outage affects everyone globally
This error often indicates a wider problem. Use our tool to verify if the site is down for everyone.
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