Installer Failed Error Message

There are a few reasons why you could receive an "Installer Failed" error message while running the custom installer:

You don't have enough space on your hard drive. Sunday Keys for MainStage requires at least 20 GB of hard drive space during installation, and the final install size is 15GB of hard drive space. Sunday Keys for Ableton Live requires at least 34 GB of hard drive space during installation, and the final install size is 22 GB. You'll want to be sure you aren't super close to that limit. This is the most common reason you might receive that error and clearing up space should correct it. We recommend you move other files to an external drive or cloud storage if you need to, it's best for your music files to stay on your computer's hard drive if at all possible so MainStage can find them. Check out this article for more.
If you have less than 8GB of RAM it would give a warning, but shouldn’t fail the install. Sunday Keys 2021 requires at least 8 GB RAM for solid performance.
If your OS is earlier than macOS 10.12 it will also cause the installer to fail. You'll need to be using Sierra OS or later.
If you are new to MainStage, you'll want to make sure you've downloaded and installed MainStage 3 from the Apple App store onto your computer. The installer needs the Music > MainStage folder there to install into, so that's needs to have been already created.
It's also possible that the installer is getting stuck at the custom icons that are now included in Sunday Sounds products. Create a new folder in this path called Custom Icons: Music-->Audio Music Apps-->Custom Icons and then run the installer again.

If you've checked all these things and still are receiving an "Installer Failed" error message, reach out to us and let us know what you've tried so far and also grab the log files that the installer writes. This article shows the exact steps we’d need to get those.