last time I saw such an error message, it turned out the network hardware was defective; on a similar occasion, it was the ethernet stack driver to be buggy. Do you have a chance to try your same configuration and stack on a different machine?
I would like to thank you. Yes, the problem was as you supposed. Now it works.
Great! good to see this confirmed, as I've only been able to see it three times (counting you) in 5 years.