If it successfully opened then the issue is resolved and the issue was actually with your previous project.

Afterward, Save and reopen the project.

Add some Audio or Plugin/connect an instrument.

Create a new project by opening your GarageBand application.In such cases, you can always try creating a new project to see if the issue is true with your project or something else is causing it. There may be a possibility that the project you are trying to open is either corrupt or damaged. If there was no update or the update did not resolve your issue then move onto the methods below. Click the Update button to install the update.If an update is available for GarageBand then it will be shown there. In the App Store, select the Updates option from the left Tool Bar.Click the Apple icon on the top menu bar.You need to open Apple App Store to update GarageBand.In case you haven’t updated your GarageBand app to the latest version then we highly recommend you do it so by following the steps below: This is an obvious step that might solve your issue.

Let’s now look at some of the potential solutions which can help you solve this issue. Corrupt Project – Your GarageBand project might be corrupt due to which your project is unable to open.Incompatible External Interfaces – There is a possibility that an external audio interface might be incompatible or malfunctioning due to which GarageBand is behaving unexpectedly.Custom Preferences – Custom GarageBand preferences might be interfering with your project files, presets, or patches.Outdated Software – Your GarageBand application might not be up to date which results in this issue.

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