Resolution

This may happen if you install a new ReWire application after you have created a project or template. Internally, Logic indexes ReWire channels alphabetically. For example, if you create a project or template with ReWire channels from Reason and then install Ableton Live, the channel strips may no longer route from Reason because Logic would index the ReWire channels from Ableton Live before Reason.

To resolve this issue, you can reassign the Aux inputs for your project or template's ReWire channel strips to match the current state of your system.

You can also work around this issue by following these steps:

1. Quit Logic.
2. In the Finder, go to /Library/Application Support and delete the alias "Ableton Live Engine."
3. In the Finder, choose Go > Go to Folder from the menu.
4. Type ~/Library/Application Support  in the "Go to the folder" field.
5. Press the Go button
6. Delete the alias "Ableton Live Engine".

This will not remove Ableton Live from your computer, but will keep Logic from seeing it as a ReWire client. 

Note: The next time you open Ableton Live after performing these steps, the alias will be recreated and Ableton Live will be available again to Logic via ReWire.

If you have this issue after installing other ReWire clients, you may be able to resolve it in a similar way. Look for the application's ReWire engine alias in a subfolder under /Library/Application Support and under ~/Library/Application Support. If you are not able to find the alias, refer to the product documentation for that application.