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JSI Tip 0914. WSAENOBUFS (10055) error.

If you take out your Captain Video Secret Decoder Ring, it becomes clear that this means:

An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full.

Not much better.

If you are trying to use an ephemeral (short-lived) TCP port above 5000, this may explain the message. By default, Windows NT 4.0 only supports 5000 ephemeral TCP ports.

You can increase this by navigating to


Add Value name MaxUserPort, a type REG_DWORD, and set it to some decimal number in the range of 5000 - 65534.

Once a port is closed, it takes 4 minutes (240 seconds) before the system will reuse it. You can alter this behavior if you

Add Value name TcpTimedWaitDelay as a type REG_DWORD and set it to some decimal number in the range of 30 - 300 seconds.

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