Use startup modifier keys with Logic Pro for Mac
If Logic Pro stops responding or quits unexpectedly when you open the app, use startup modifier keys to troubleshoot the issue.
To enter one of the troubleshooting modes described in this article, go to your Applications folder, double-click the Logic Pro app, then hold down the respective modifier key(s) until a dialogue appears or Logic Pro opens.
Open Logic Pro without audio or plug-ins
Press the Control key while the app is opening, then choose one of these options:
If you click Launch, Logic Pro will open normally.
If you click Don’t Launch, Logic Pro will open with Core Audio disabled and therefore won’t have audio input or output. This can be helpful to rule out issues with a specific Core Audio driver, especially if you're using an external audio interface. In some cases, Logic Pro may stop responding or quit unexpectedly while initialising Core Audio. If Logic Pro opens when you choose Don’t Launch, you may need to update or service your external audio interface.
If you click Launch Without Audio Units, Logic Pro will open with Core Audio enabled, but all Audio Units plug-ins disabled. This can be helpful for troubleshooting issues with plug-ins, especially third-party plug-ins.
Open Logic Pro in Audio Units safe mode
Press Shift-Control to open Logic Pro with only validated Audio Units plug-ins enabled.
If you’ve installed Audio Units plug-ins that have failed the Audio Units validation scan, open Logic Pro in this mode. The validation scan will take place automatically when Logic Pro is first opened, when you install new plug-ins or update existing ones.
Open Logic Pro without automatic startup actions
Press Option when opening Logic Pro to open Logic Pro without automatically loading the most recent project, the Open dialogue, Templates dialogue or any other option as set on the Project Handling pane of the Logic Pro > General > Settings window.
This can help rule out issues that may be caused by the currently loaded project. For further troubleshooting, press the Option key then choose File > New to load an empty default project.