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ERR_CONNECTION_RESET: Causes and Fixes

The connection opened but was abruptly closed, usually by something between you and the server: security software, a proxy or VPN, a firewall, or a flaky network.

ERR_CONNECTION_RESET

The connection to the server was cut off suddenly: a TCP reset arrived from the server or from something in between, such as a firewall, proxy or security software.

Quick checks

  • Reload the page once: one-off resets happen on unstable networks.
  • Try another network or mobile data.
  • Pause your VPN, proxy and antivirus web protection, then retry.
  • Try a private window to rule out extensions.

Fixes on Mac

  1. Turn off VPN, proxy and filtering apps

    1. Disconnect VPNs and quit proxy apps like Charles or Proxyman.
    2. System Settings › Network › Wi-Fi › Details › Proxies: turn off unused proxies.
    3. System Settings › General › Login Items & Extensions › Network Extensions: check for content filters you don't recognise.

  2. Clear Chrome's sockets and cache

    1. Open chrome://net-internals/#sockets and click Flush socket pools.
    2. Delete cached images and files in Chrome's settings.

  3. Lower the MTU if large pages fail

    1. If small pages load but big ones reset, a VPN or PPPoE link may have a lower MTU.
    2. System Settings › Network › Ethernet or Wi-Fi › Details › Hardware › Configure Manually, set MTU to 1400 and test.

Fixes on Windows

  1. Reset Winsock and TCP/IP

    1. In an administrator Command Prompt: netsh winsock reset, netsh int ip reset, ipconfig /flushdns.
    2. Restart the PC.

  2. Check antivirus HTTPS scanning

    1. Antivirus products that scan HTTPS traffic can reset connections. Turn off web or HTTPS scanning briefly to test.

Other devices

  1. Router and network

    1. Restart the router and modem.
    2. Update the router firmware; some routers reset long or large connections.

Still not working?

If one site resets on every network and device, the problem is on the server side: a web application firewall, a crashing backend or a load balancer closing connections. Site owners should check server and proxy logs for resets at the time of the failure.

If many sites reset only on your network, suspect the router, the ISP or network-level filtering (school, office, country-level blocking).

See what’s happening

LightAtom's connections view shows whether your browser connects to a proxy address instead of the site's servers, and which process runs that proxy.

Frequently asked questions

What causes ERR_CONNECTION_RESET?

Something sent a TCP reset that closed the connection. Common sources: security software, VPNs, proxies, firewalls, MTU problems on VPN links, and servers or load balancers closing connections.

How do I fix ERR_CONNECTION_RESET on a Mac?

Disconnect VPNs and proxies, check for content-filter network extensions, flush Chrome's socket pools, and test on another network. If only large pages fail, try a lower MTU.

Is ERR_CONNECTION_RESET a virus?

Rarely. It's normally caused by network software or the server. Unknown network extensions or proxies you didn't install are worth investigating, though.

What is a TCP reset?

A packet with the RST flag, which tells the other side to abort the connection immediately. Servers send it when they reject or crash; middleboxes send it to block traffic.

Related errors and tools

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LightAtom team

The people who build LightAtom, a network monitor for macOS.