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leveldb assert() fail on Windows as per screenshot.

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Official Windows v0.16.0 release.
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The last debug.log entry before the crash:
2018-05-27 08:21:41 UpdateTip: new best=000000000000000000071dfc4ed27cdfb03559f91a7470bc9863ae0e62a2991c height=524611 version=0x20000000 log2_work=88.894279 tx=318748815 date='2018-05-27 08:19:51' progress=0.999999 cache=62.6MiB(378174txo)