ERR_CONNECTION_RESET — Connection Reset in Chrome

Enterno.io Editorial Team

ERR_CONNECTION_RESET: Causes & Fix

By Anatoly Oshmanovsky · Updated Apr 17, 2026

Key idea:

ERR_CONNECTION_RESET means Chrome received TCP RST during TLS handshake or active session. Causes: firewall (local or ISP) drops a packet, antivirus with TLS inspection mangles the handshake, overloaded server where the kernel kills the connection, DPI systems blocking a specific SNI. Fix: disable AV TLS inspection, verify server reachability, try via VPN.

This error blocks HTTPS access. Below: causes, fixes, working config, FAQ.

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Common Causes

Local firewall / Kaspersky TLS inspection cuts packets
ISP-level DPI blocks SNI by domain (common in certain regions)
Server overloaded, kernel TCP accept queue overflowed
Wrong path MTU — TCP segments get dropped
Web process crash (nginx/Apache worker) mid-handshake

Step-by-Step Fix

Disable antivirus TLS inspection for 10 minutes — retest
Reboot the router (sometimes it cuts connections)
Try via VPN or mobile — if it works = ISP DPI
On the server: ss -ltn to confirm listener. dmesg | grep -i tcp — OOM?
Increase net.core.somaxconn and nginx backlog=1024

Check SSL Certificate →

Related SSL Errors

CertificateExpiry, issuer, domains (SAN)

ChainIntermediate and root CA validation

TLS ProtocolTLS version and cipher suite

VulnerabilitiesHeartbleed, POODLE, weak ciphers

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Common Mistakes

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Expired certificateBrowsers block sites with expired SSL. Set up auto-renewal or monitoring.

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Incomplete certificate chainWithout intermediate CA, some browsers and bots cannot verify the certificate.

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Mixed content on HTTPS siteHTTP resources on an HTTPS page — the browser lock icon disappears, reducing trust.

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Using TLS 1.0/1.1Legacy TLS versions have known vulnerabilities. Use TLS 1.2+ or 1.3.

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Domain mismatch in certificateThe certificate must cover all site domains, including www and subdomains.

Best Practices

✓

Set up auto-renewalLet's Encrypt + certbot with cron — certificate renews automatically every 60-90 days.

✓

Enable HSTSStrict-Transport-Security header forces browsers to always use HTTPS.

✓

Use TLS 1.3TLS 1.3 is faster (1-RTT handshake) and safer — legacy ciphers removed.

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Monitor expiration datesCreate a monitor on Enterno.io — get notified well before expiration.

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Verify chain after renewalAfter certificate renewal, confirm that intermediate certificates are installed.

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How-to

Glossary

Research

TLS Cipher Suites 2026: Distribution Report

Errors

Alternatives

Frequently Asked Questions

How is it different from ERR_EMPTY_RESPONSE?

ERR_EMPTY_RESPONSE — server accepted connection but sent nothing. ERR_CONNECTION_RESET — the connection was torn down by an RST packet.

How do I know if it's ISP blocking?

Try via VPN. If VPN works — ISP. If it fails everywhere — server side.

Browsers show ERR_CONNECTION_RESET or ERR_CONNECTION_ABORTED — which?

ABORTED = client cancelled (redirect/close). RESET = RST packet from the other side (server/proxy/DPI).

How do I check reachability?

<a href="/en/ping">Enterno Ping + Port Checker</a> — tests TCP 443 from multiple regions + monitoring.