It's literally impossible for me to boot up the game. Then it deletes itself.
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It ran fine on mine and I'm running an older OS so I don't think compatibility is the issue. The only thing I can think is that there are two files in the folder called Celeste64, you want to open the one that's .exe, not the .pdb file. Assuming you're on Windows, of course. If you're on Mac or Linux, I'll be much less helpful.