Remove, disable, or rescan macOS Audio Units plug-ins in Logic Pro for Mac or MainStage
Learn what to do if you're using third-party Audio Units plug-ins and Logic Pro or MainStage isn't working properly, or if you can't find a recently installed plug-in.
Try these recommendations depending on what you're experiencing:
If you can open Logic Pro or MainStage but you're having issues with your project or concert, remove Audio Units plug-ins from your project.
If you can't open Logic Pro or MainStage, disable Audio Units plug-ins.
If you can't find a recently installed plug-in, restart your Mac, confirm the plug-in is installed, and rescan your plug-ins.
Before you start troubleshooting Audio Units plug-ins, check with the manufacturer to see if the plug-in is compatible with your version of macOS and if an update is available.
Remove Audio Units plug-ins from your project or concert
If you're having an issue in a particular Logic Pro project that uses Audio Units plug-ins, open Logic Pro without Audio Units plug-ins first. If that fixes your issue, you can then remove individual Audio Units plug-ins from your project to determine if a particular plug-in is causing the issue.
If you're having an issue with a MainStage concert, start troubleshooting by removing individual Audio Units plug-ins from the concert.
Open Logic Pro without Audio Units
Quit Logic Pro if it's open.
Open Logic Pro and immediately press and hold the Control key before a project opens.
In the alert, click Launch Without Audio Units.
Open the project you're troubleshooting.
If this resolves the issue, remove individual Audio Units plug-ins from your Logic Pro project.
If this doesn't resolve the issue, try other troubleshooting methods.
Remove individual Audio Units plug-ins from your Logic Pro project or MainStage concert
If opening Logic Pro without Audio Units fixes your issue in Logic Pro, remove each Audio Units from your Logic Pro project to isolate the plug-in that's causing your issue. You can also use this method to troubleshoot Audio Units plug-ins in MainStage.
If you opened Logic Pro without Audio Units, close Logic Pro.
Open Logic Pro or MainStage, then open the project or concert you're having issues with.
Save a copy of your project or concert.
Close the original project or concert.
Open the copy of the project or concert, then remove one Audio Units plug-in from the project or concert:
Place the pointer over the slot of a channel strip that contains an Audio Units plug-in.
Click the arrows that appear to the right.
Choose No Plug-in from the pop-up menu.
Try to recreate the issue.
If the issue isn't resolved, remove another Audio Units plug-in, testing after each time you remove a plug-in.
If the issue is resolved, reinstall the plug-in or check with the manufacturer for updates or further support. You can also replace the plug-in with a similar plug-in from Apple or a different manufacturer.
Disable Audio Units plug-ins
If you can’t open Logic Pro or MainStage, move the installed files for third-party Audio Units plug-ins. You might also want to move a plug-in file if you found that a particular plug-in is causing an issue in a project.
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 can't find the files in that location, 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 might be causing the issue, locate the file for the plug-in in the folder, then drag the file to the Desktop or another location, such as a folder dedicated for this procedure.
Restart your Mac.
Try to reopen Logic Pro.
If you still can't open Logic Pro or MainStage:
Create a new folder on the Desktop.
Move all 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-at-a-time. Quit and reopen the app after you replace each plug-in file.
If you can't open the app after replacing a particular plug-in file, that plug-in might be corrupted or incompatible. Try reinstalling the plug-in or check with the manufacturer for 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 the steps in this section in order until your plug-in is available.
Restart your Mac
If your Mac is running macOS High Sierra or later and you 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 that the plug-in is installed.
Make sure that the plug-in is installed
Use the Plug-in Manager to check if the plug-in is 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 column.
If “not authorized” appears in the Compatibility column for the plug-in, make sure the plug-in is properly authorized 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 by manufacturer, click manufacturer's name in the left 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 authorized” appears in the Compatibility column for the plug-in, make sure the plug-in is properly authorized as documented by the manufacturer, then rescan the plug-in.
If the plug-in fails validation again, check with the manufacturer to see if the plug-in is compatible with your version of macOS and for possible updates.
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 Plug-in Manager. Resetting Audio Units in Logic Pro also resets 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 rescans 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 if the plug-in is compatible with your version of macOS, and for possible updates.
Rescan Audio Units plug-ins in all apps
As a last resort for troubleshooting any app that has validation or other issues with a specific Audio Units plug-in, manually remove AudioUnitCache files to force a full rescan. You can also do this to rescan MainStage plug-ins if you don't also use Logic Pro on the same Mac.
This process can be lengthy. You won't be able to use any applications that use Audio Units for the duration of the scan.
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 AudioUnitCache folder to the Desktop or another location, such as a folder dedicated to this procedure.
Restart the computer, then open MainStage. All installed Audio Units plug-ins are rescanned. If the plug-in is still not available, check with the manufacturer to see if the plug-in is compatible with your version of macOS, and for possible updates.
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