Fixing the "app is damaged" warning

macOS loves this warning. Most of the time the app is fine and the system is mad that you downloaded it from a browser instead of the company store. Here is the path I actually use, and the point where I stop and treat it as a real problem.

Why the warning shows up

A download gets a quarantine mark. Gatekeeper reads that mark and, on a bad day, phrases it like the file is corrupt. I have seen it on Compresto, on audio utilities, on a font installer, and on a game a cook brought in on a drive. The common thread was the download, not the restaurants.

I am not interested in turning security off for the whole Mac. One app, one exception, then we go back to service.

The clicks

1. Leave the app in Applications. Don't run it from the disk image and then lose the disk image.
2. If a normal double-click shouts, don't keep double-clicking. That doesn't wear it down.
3. Right-click the app (or control-click) and choose Open.
4. Read the second dialog. If it offers Open again, that's the one that clears the mark for this app.
5. If you already dismissed it, go to System Settings, then Privacy & Security, and scroll until you see the app named with an Open Anyway button. Use it once.

The menu path, so you can find it without me on the phone:

System Settings → Privacy & Security → Open Anyway

After that, a normal double-click should be enough. You do not have to right-click it for the rest of its life.

If the only button is Move to Trash

That dialog is the dramatic one. Cancel it. Don't trash the app because a button was big and red. Go do the right-click Open path above. If Open isn't in the right-click menu, the thing you downloaded may be a disk image you haven't opened, or a zip you haven't unpacked. Open the dmg, drag the app to Applications, and start over from there.

When it really is damaged

If the right-click path fails twice, and Privacy & Security never mentions the app, download it again from the button on the program page. A half-written file does happen, usually because someone force-quit a browser on a diner wi-fi. Compare the size to the number I printed. If I said 11 MB and you have 2 MB, you don't have the app. You have a stub.

I don't keep a second, secret way to turn warnings off for every file on the Mac. If a page on the internet tells you to disable the checks system-wide so a game will launch, close that page. One app is a decision. The whole Mac is how you get a worse Saturday.

How I update an app after that

When a new version shows up on this board, I download it, I open it, and I only then throw out the old one if the new one actually launched. Replacing first is how you end a night with no compressor and a folder of four-megabyte JPEGs.

• Read the version on the right of the row. That's the one the page is about.
• Older builds, when I kept notes, live under Previous versions on the program page.
• Match the chip. An Intel build on an M-series Mac is not "updated." It's the wrong plate.

Related: Compresto 1.31, which is where this warning bit me last spring, and where the install window points back to this note.