If you can't find a recently installed plug-in for Logic Pro for Mac or MainStage
Learn what to do if you installed a third-party Audio Units plug-in but it's not appearing in the Logic Pro or MainStage plug-in slots.
Confirm that the plug-in is installed
Reset all Audio Units in Logic Pro and MainStage
Rescan Audio Units plug-ins in all apps
Restart your Mac
If your Mac is running macOS High Sierra or later and you recently installed a plug-in that you can't find 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. Make sure to check the sub-menus, where plug-ins are organized by manufacturer.
If the plug-in still isn't available in Logic Pro or MainStage, confirm that the plug-in is installed.
Confirm that the plug-in is installed
Use the Plug-in Manager to confirm that 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 the 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.
Learn more
Remove or disable Audio Units plug-ins in Logic Pro for Mac or MainStage
If Logic Pro for Mac isn't working