Try starting Winlogbeat in the foreground (not as a service) and see if there are any errors. This is similar to what we recommend in the Getting Started guide to test the configuration prior running it as a service, but this will actually run it with full debug enabled.
PS C:\Program Files\Winlogbeat>.\winlogbeat.exe -c winlogbeat.yml -e -v -d "*"
If that doesn't get you anywhere, then post your configuration here.