Try these recommendations depending on what you're experiencing:
- If you can open Logic Pro or MainStage but you're experiencing issues with your project or concert, try bypassing plug-ins.
- If you can't open Logic Pro or MainStage, try removing plug-ins.
- If you can't find a recently installed plug-in, restart your Mac, confirm the plug-in has been installed and rescan your plug-ins.
Bypass Audio Units plug-ins
If you're experiencing an issue in a particular Logic Pro project or MainStage concert that uses third-party plug-ins, bypass each third-party plug-in in the project one by one, testing the project after you've bypassed each plug-in.
You can bypass plug-ins in several different ways:
- Place the pointer over the plug-in slot in a channel strip, then click the Bypass button
so the slot dims. - Option-click the plug-in slot so the slot dims.
- In the plug-in window, click the Bypass button so the slot dims.
If bypassing a plug-in fixes your issue, check with the manufacturer to find out whether the plug-in is compatible with your version of macOS and if there are any updates available.
Remove Audio Units plug-ins
If you can't open Logic Pro or MainStage, remove the installer files for third-party Audio Units:
- Find the installed plug-in file on your Mac:
- From the Finder menu bar, choose Go > Go to Folder, type "/Library/Audio/Plug-Ins/Components" into the Go to Folder field, then click Go.
- You can also check the Library in your Home folder. From the Finder menu bar, choose Go > Go to Folder, type "~/Library/Audio/Plug-Ins/Components" into the Go to Folder field, then click Go.
- If you suspect a particular plug-in may be causing the issue, locate the file for the plug-in in the folder, then drag the file to the Desktop.
- Try to reopen the app.
If you still can't open Logic Pro or MainStage:
- Create a new folder on the Desktop.
- Move all of the plug-in files that appear in their installation locations to the new folder.
- Try to open Logic Pro or MainStage.
- If you can open the app, replace each plug-in file to its original location one by one. Exit and reopen the app after you've replaced each plug-in file.
- If you can't open the app after replacing a particular plug-in file, that plug-in may have been corrupted or is incompatible. Try reinstalling the disabled plug-in or check with the manufacturer to see if there's an update.
Find a recently installed plug-in for Logic Pro or MainStage
If you installed a third-party Audio Units plug-in but it's not available in Logic Pro or MainStage, try following the steps provided in this section in the order they're listed until your plug-in is available.
Restart your Mac
If your Mac is running macOS High Sierra or later and you've recently installed a plug-in that isn't available in Logic Pro or MainStage, restart your Mac. Before you restart your Mac, confirm that the plug-in is 64-bit compatible. 32-bit plug-ins aren't compatible with Logic Pro or MainStage.
- Choose Apple menu > Restart.
- Open Logic Pro or MainStage.
- Click an Audio Effect, Instrument or MIDI Effect slot to see if the plug-in is available in the pop-up menu.
If the plug-in still isn't available in Logic Pro or MainStage, make sure the plug-in has been installed.
Make sure the plug-in has been installed
Use the Plug-in Manager to check if the plug-in has been installed.
- Choose Logic Pro > Settings (or Preferences) > Plug-in Manager, or MainStage > Settings (or Preferences) > Plug-in Manager.
- In the Plug-in Manager, locate the plug-in. To filter the list by manufacturer, click the manufacturer's name in the left-hand column.
If "not authorised" appears in the Compatibility column for the plug-in, make sure the plug-in has been authorised correctly as documented by the manufacturer. - Reinstall the plug-in, then restart the computer.
- Open Logic Pro or MainStage, then check the Plug-in Manager to see if the plug-in appears there. If it does, open a project or concert and make sure the plug-in is available.
- If the plug-in appears in the Plug-in Manager but is not available in a Logic Pro project or MainStage concert, rescan the plug-in.
- If you still can't find the plug-in in the Plug-in Manager, reset all Audio Units.
Rescan a plug-in
If the plug-in appears in the Plug-in Manager but still isn't available in Logic Pro or MainStage, rescan the plug-in.
- In the plug-in Manager, locate the plug-in you want to check. To filter the list by manufacturer, click manufacturer's name in the left-hand column.
- If "failed validation" appears in the Compatibility column for the plug-in, select the plug-in in the list, then click Reset & Rescan Selection.
If "not authorised" appears in the Compatibility column for the plug-in, make sure the plug-in has been authorised correctly as documented by the manufacturer, then rescan the plug-in. - If the plug-in fails validation again, check with the manufacturer to find out whether the plug-in is compatible with your version of macOS and if there are any updates available.
- If the plug-in doesn't appear in the plug-in manager, try resetting all Audio Units.
Reset all Audio Units in Logic Pro and MainStage
If you can't find a recently installed plug-in in the Plug-In Manager in Logic Pro or MainStage, try resetting all Audio Units using the Logic Pro Plug-in Manager. Resetting Audio Units in Logic Pro will also reset them for MainStage.
- Choose Logic Pro > Settings (or Preferences) > Plug-In Manager.
- Click Full Audio Unit Reset.
- Close Logic Pro, then reopen it. Logic Pro will rescan all installed Audio Units plug-ins.
- Check Logic Pro or MainStage to see if the plug-in is available.
If the plug-in is still not available, check with the manufacturer to see whether the plug-in is compatible with your version of macOS and if there are any updates available.
Rescan MainStage plug-ins only
If you only use MainStage and don't have Logic Pro installed, remove files manually to rescan all Audio Units in MainStage:
- In the Finder, press and hold the Option key, then choose Go > Library.
- In the Finder window that opens, locate the AudioUnitCache folder in the Caches folder.
- Move the files from the AudioUnitCache folder to the Desktop.
- Restart the computer, then open MainStage. All installed Audio Units plug-ins will be rescanned.
If the plug-in is still not available, check with the manufacturer to see whether the plug-in is compatible with your version of macOS and if there are any updates available.