dedicated server -logFile output.log generates error

I have replicated the Fusion dedicated server example: https://doc.photonengine.com/fusion/current/technical-samples/dedicated-server/fusion-dedicated-server#api

on Unity 2021.3.20f1, and built it as a dedicated server. When I run the built exe with:

.\build.exe -batchmode -nographics -logFile output.log

I get the error:

CreateDirectory '' failed: The system cannot find the path specified.

 (current dir: )

This prints twice, and then execution pauses. I have attached a screenshot of my terminal output following the command to start the server:


Any ideas on how to fix this? I am thinking its a photon bug.