Hi. This has not helped me. But I googled "clearing quarantine attribute" and found this article, which solved my problem: https://derflounder.wordpress.com/2012/11/20/clearing-the-quarantine-extended-attribute-from-downloaded-applications/ In short: I opened the terminal and typed sudo xattr -r -d com.apple.quarantine /Applications/Hexen\ II/ And it works as a charme!