2.4.3.22. Error ERR_SPDY_PROTOCOL_ERROR

The problem can be observed in Chromium-based browsers (Chrome, Opera, Vivaldi, Brave and others) running on devices that use anti-virus programs like AVG or Avast, especially when using an SSL connection.

  • If you are using any of the antivirus programs1), try disabling HTTPS scanning in it, or adding the error site to exceptions. For example, to add a site to the exclusions in Avast, do the following:
    1. Go to section "Settings" ("Settings").
    2. Youaretaking "Active defense" ("Active Protection").
    3. Openup "Web screen settings" ("Web Shield Protection").
    4. In chapter "Exceptions" add the sites where the error occurs.
    5. Check for an error.
  • Try to clear the socket pool in Chrome:
    • Enter in the address bar of your browser chrome://net-internals/#sockets.
    • Click "Flush socket pool":
    • Restart your browser and check for the error.

1)
To check if the antivirus you are using is the source of the problem, you can temporarily disable it and check if an error occurs.
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