The Compiler.exe file could not be loaded and the server could not be opened. I want to know how to solve this problem.

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Compiler.exe display size is 0 bytes

Compiler.exe is downloaded and installed when you start your server.  Ensure your firewall isn't blocking the download (port 80), usually there is a message on server start if there is a failure obtaining the file.  Try restarting and let us know if you see any messages related to Compiler.exe.

As a temporary measure you can download it manually here.