Well, the PS script crashed just after attempting to load miners. Here are the last few lines from the miner.log:
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Last Refresh: 02/18/2018 05:55:16
Sleep 240 sec
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Stats ' X17 ' -> 41.68 MH after 27243 sec
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Loading BTC rate from 'api.coinbase.com'..
Loading pool stats..
Loading miners..
PS>TerminatingError(): "The pipeline has been stopped."
>> TerminatingError(): "The pipeline has been stopped."
PS C:\Users\ONDA-1\Desktop\Mining\NPlusMiner-1.2.1> exit
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Windows PowerShell transcript end
End time: 20180218060008
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I did not press Ctrl-C, even though that is what it looks like. I did type in 'exit' when I noticed it was sitting at the PS command prompt.
EDIT - I should also note that ccminer-polytimos was still plugging away on X17, so this wasn't a fatal error.