Deleting a Previous System folder
Reader Jacob Franks is curious about a folder he’s found on his Mac. He writes:
I discovered a folder called Previous System on my iMac. What is it and is it safe to delete?
This file is the result of you performing an Archive and Install installation of the Mac OS at some time. When you did that, the installer placed a variety of system files—preference files, fonts, and plug-ins among them—in this Previous System folder. You can’t boot your Mac from this folder, it’s there simply for the storage of old system files.
The idea is that if you find that your Mac performs oddly after installing the new system—it’s missing some beloved fonts or plug-ins, for example—you can rummage around in this folder and retrieve the goodies you’ve lost. If you’ve run your Mac for a good amount of time—a month or more—and everything seems hunky dory, you’re safe to toss out this Previous System folder. On the other hand, if you’re the careful type and you don’t need the space you’d gain by giving this folder the heave-ho, you can keep it right where it is. It’s doing no harm.