Profile doesn't include the com.apple.security.app-sandbox entitlement.

The com.apple.security.app-sandbox entitlement is only relevant on macOS, where it enables the App Sandbox. On macOS it’s an unrestricted entitlement, which means it doesn’t have to be authorised by a profile. See TN3125 Inside Code Signing: Provisioning Profiles for the backstory to this.

The fact that someone is complaining that this is not authorised by a profile suggests that you’re trying to use it on iOS, or one of its child platforms. This is not necessary — iOS apps are always sandboxed, it’s not an opt in like on macOS — and won’t work.

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I am also getting this error when clicking the "Validate App" in the Organizer window. I am trying to validate an iOS app not macOS, so not sure why this error message would appear. Is it possible one of my settings in the profile or project is set to macOS when it shouldn't?

Is it possible one of my settings in the profile … is set to macOS when it shouldn't?

No.

or project

Yes. It seems likely that something has enabled the App Sandbox entitlement in your iOS target.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"