If you start influxd in the foreground (i.e. executing influxd from a command prompt), it normally writes logs to standard error.
I don’t have experience running InfluxDB with Windows, so I’m not sure how people are running it as a service or where logs would normally be expected to be sent to. Unfortunately nothing relevant is turning up on any searches I’ve tried. I assume the logs are going to whatever place is standard for how the influxd service is starting.
