@danieltak Don't believe everything you read on the internet. What's the big rush to get it working on Stretch anyway? What is it going to give you that Jessie doesn't? Stick with what works until RetroPie has been fully tested to work with Stretch and gets an official release and support.
I'm not offended, I just think it's odd that someone would see an error message saying a certain OS version is not supported and then come to the official forum seeking support!
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