The .NET configuration file created in Visual Studio, called myService.exe.config , must be saved in the same location as exe. and this XML not an ini file.
Log files can be saved in a folder like C:\Logs\ServiceName or something else that you like, we usually create a network share in such a folder so that we can check log files from other computers as well, without having to connect to the server, where is the windows service running.
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