Help · Is it safe to delete?
What is com.apple.quarantine?
When you download a file, macOS tags it with com.apple.quarantine. It tells Gatekeeper to check the file the first time you open it, which is when you see “downloaded from the internet” warnings.
Safe to remove? Leave it alone. It takes no space and protects you. Removing it skips Gatekeeper's first-run check, so never remove it from anything whose source you're not sure of.
If an app won't open
Use the supported route: System Settings › Privacy & Security, then Open Anyway for an app you trust. Be wary of any website or "support" person telling you to paste a command to remove quarantine: it's a common trick used to install malware. More: installing a Mac app safely.
Sources: Eclectic Light Company, 5 Dec 2025; macOS xattr manual page. Checked October 2026.
Know what's on your Mac.
Pangalin Space Manager's free scan shows what's using your disk and explains it, with no Terminal and nothing removed without your say. Notarised by Apple, so it passes Gatekeeper's check.
Free to scan · first 5 GB freed free · Notarised by Apple · Apple silicon, macOS 13 or later