Some incompatible software is automatically disabled when you upgrade macOS.
When you upgrade macOS or migrate content to a new Mac, software known to be incompatible with the new macOS version is set aside and won’t run on your updated system. The software is moved to a folder named Incompatible Software, at the top level of your Mac startup disk.
If you want to use one of the incompatible apps, get an updated version that's compatible with your new OS. Apps in the Mac App Store list their compatibility and system requirements on their product pages. You can also check with the app developer to find out if they have a new, compatible version or plan to release one.
PowerPC applications won't run on OS X Mavericks or later.
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