What programs exist to find and delete "orphan files" left after deleting an Application?

I have transferred my system from Mac to Mac for over 15 years. I have preference files and other plists lurking around in my system for programs I tested years ago.

Is there a smart program that could point me to these orphan files knowing that the application that created them is not on my system?

If you are willing to use Terminal.app you can use find to identify files/folders which haven't been accessed for a long time.

• find ~/Library/Preferences -atime +52w will list all prefences which haven't been accessed in the last 52 weeks.
• find -d ~/Library/Preferences -atime +52w -ok rm '{}' \; will ask whether you want to delete it file by file

and if you don't want to get asked for each file, run

find -d ~/Library/Preferences -atime +52w -delete

OnyX has several cleaning options and might be worth a try.

Other than that, you could check the installation receipts in /Library/Receipts and ~/Library/Receipts. Applications that are installed via installers should write to this directory with what they've installed and where. You could inspect this for programs that you've 'uninstalled' and manually remove the lurking files.

I'm not connected to the company but if you want a paid app In the past I have used App Zapper.

It is a drag and drop app. You drag the app to the window and it shows all dependencies for you to delete or not. I did a clean install for ML so I haven't used it in quite some time and I'm afraid I don't recall the cost but I remember it was not expensive. UPDATE: It cost $12.95; More than I remembered.

Perhaps Pacifist could be used; Open the uninstalled version of the app in Pacifist (drag it there) and look to see what gets installed, then remove those items?