I have a similar "connection lost" problem that some others reported previously.
I am running NJ with Kinetick (for data) and IB (for trading) and I realized that Kinetick and IB were disconnected and reconnected a few times in a day. And at some point, chart did not update in real time and trading did not occur. But NJ showed that kinetick and IB were still connected.
I restarted NJ and established connection with Kinetick and IB again. Then the data feeding was working properly.
Some background on my system is following.
1. Windows 7
2. My computer has a fixed IP
3. Firewall may have caused this problem but no clue (not know how to check)
I am happy to provide log, trace file.
Please help.
cu.

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