“Apple cannot check it for malicious software”: how to open the app

1. Try to open the app (or installer) once. When the alert appears, click Done, not Move to Trash.
2. Open System Settings and click Privacy & Security in the sidebar.
3. Scroll down to the Security section. You'll see a line saying the app was blocked, with an Open Anyway button. Click it.
4. Enter your login password and click OK, then click Open in the alert that follows.

macOS remembers the choice, so you only do this once per app. Here is how the three steps look when you download Toolbay's own Mac installer in a browser (it is not notarized yet):

Toolbay's download pagealso offers a one-line Terminal install for Mac. A file fetched that way is never tagged as a browser download, so this alert doesn't appear at all.

macOS shows different alerts depending on why it stopped the app. They are not all fixed the same way.

For years the shortcut was to Control-click the app and choose Open. Apple removed it in macOS Sequoia (version 15, 2024): its developer news says users “will no longer be able to Control-click to override Gatekeeper”. Every Mac on Sequoia or later has to go through System Settings > Privacy & Security instead, which is the Open Anyway route above.

• You haven't tried to open the app yet.The button only appears after macOS blocks the app. Double-click the app, click Done, then go back to Privacy & Security.
• More than about an hour has passed. Apple says the button is available for about an hour after you try to open the app. Try again to bring it back.
• Your Mac is managed by work or school. Apple notes these settings might not be available if a system administrator manages your Mac. Ask your IT team.

If macOS says the app is damaged instead, there is no Open Anyway button at all; see the Terminal step below.

Not from System Settings. Under “Allow apps downloaded from”, current macOS offers only two choices: App Store, or App Store and identified developers. There is no “Anywhere” option there. Approving one app at a time with Open Anyway is the safer habit anyway: you keep the check for everything else you download.

When you download a file, macOS tags it with a quarantine flag, and that is what triggers the check. For an unsigned app you trust that macOS reports as damaged, removing the flag lets it open. Open Terminal (Command + Space, type Terminal, press Return) and run this, with your app's name:

xattr -dr com.apple.quarantine "/Applications/App Name.app"

This skips macOS's malware check for that one app, so it is only for software whose source you trust, such as an open-source app you can inspect. Never run it on something from an unknown site or an email attachment. It is the same command Toolbay's own install notes use for our Mac apps that ship as a disk image.

Notarization means Apple scanned the app for known malware before you got it. An app without it isn't necessarily harmful — small and open-source developers often haven't paid for or finished Apple's process yet — but you lose that check, so the decision rests on where the app came from. Get it from the developer's own site, and prefer open-source apps whose code you (or others) can read.

Toolbay's Mac apps are in that situation today: they are not notarized yet, and their full source is public on GitHub under the MIT license, for example Toolbay Flow. We'll say so on each app page until notarized builds ship.