Problem on C ruby extension

Hi!
I’ve written a C program which runs good as an exe, and would like to create a Sketchup Extension from it… I’ve tried to start with the github HelloWorld project, but did not manage to create the appropriate rb file to get it work… I recieve an error message:

Error: 193: %1 ist keine zulässige Win32-Anwendung. - path of .so file
which means “is no valid” Win-32 application…

what did I do wrong?

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