“Existing Connection Was Forcibly Closed by the Remote Host”

Direct answer

A TCP connection was reset or closed unexpectedly. The message does not identify whether the client, server, router, proxy or security software initiated the reset.

Identify the failing layer

Do not disable every firewall or anti-virus rule just to test a vague reset message; use a narrow, reversible rule when necessary.

First checks and evidence

• Match the player’s timestamp with proxy and backend log entries.
• Check whether the server was restarting, a plugin kicked the account, or a reverse proxy/tunnel disconnected.

Admin diagnosis and repair

1. Have an affected player try a second network; compare with other players who remain online.
2. Only after identifying the layer, adjust its configuration or remove the problematic plugin/update in staging.

Verify the fix: Confirm stable reconnection from the original and alternate networks while recording server tick health.

References

Use the documentation for the exact software and release you run. These sources support the settings or diagnostic behavior used in this fix.

• PaperMC: Basic troubleshooting

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