I'm not sure about the threat part, it could be IPS / IDS or AV that's screwing your connection.
about the IP connection error;
This is probably due to the destination not reacting in time, hence the error. the server does not respond or isn't able to connect in time ( time-out ).
I'v seen it before with HP switches, it turned out that there was a high collision rate on the switch ( in other words, the switch was at max capacity of throughput and therefor started dropping packets ).
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