Lately when I open Garageband I get a message saying "Error initializing CoreMIDI" "Warning: MIDI services not available." In other words I'm unable to use my MIDI controller to record software instruments. Does anyone know how to correct this issue? It was working before. I have no idea why all of a sudden it's not now.

Hi - Some troubleshooting steps: - As always, do a hard shutdown/restart - Go to GarageBand Preferences > Audio/MIDI and click Reset MIDI Drivers - Check the Audio MIDI Setup utility [Applications > Utilities] -- open the MIDI pane, it should show you if the computer recognizes the MIDI keyboard [there's a 'test" button" as well] - Check the USB connection -- if you've changed it, go back to the previous connection and see if that restores functionality - Try a different USB cable - Did the keyboard require you to install a MIDI driver? If so, try re-installing it - Try blowing out GarageBand's Preferences - This was a bug in Logic a couple years back [and GB is based on Logic] -- if you're running an older version of GB maybe try updating it..?

Hey Joe A, Thanks for the response. #1; Yeah that's when the message shows up. Every time I do a "hard shutdown/restart". I might add that this message occurs BEFORE I even have the MIDI controller plugged in. Which causes me to think It must not have anything to do with the USB cable. Seems like the Error occurs while GB is booting up. #2; I just tried that "Reset MIDI Drivers" and that didn't do anything. #3; I found the Audio MIDI Setup Utility but curiously when I open that I'm only seeing a page for Audio in/out. There's no tab for any kind of MIDI at all? Could it be because my interface (UA Apollo twin) doesn't have a MIDI through function? I just have a dirt simple Korg MicroKey controller that's USB powered, plugged directly into the computer. I don't know it was working before.... ?? I did have to replace my HD about 6 months ago. Could it be that that app (Audio MIDI Setup) somehow got corrupted? #4; Good question about installing or re-installing drivers. It's been almost 10 years since I got the controller so I don't even recall if there was a driver to install. I'll have to check with Korg and see about that. #5; Not sure what you mean about "blowing out" GB's preferences? #6; Yeah I have the latest update for GB. Thanks again for your in depth response!!

Hi - So, re #3. .In Audio MIDI Setup there's a second window showing the current configuration of MIDI devices -- if it's not showing, go to the Window menu and select Show MIDI Studio. Re #5.. All applications maintain a Preference file, with the settings you dial up in that program's Preference panels [i.e. GB > Preferences menu]. Sometimes this file get corrupted, and if you remove it the application will automatically create a fresh one, which occasionally solves unexplained problems. However, GB seems to manage this differently - I can't find them in the usual location, and an Apple Help document sends you to the Terminal [!] to reset them, so forget about that.. I'd lean to #4, check w/ Korg on the need for a [new/updated] MIDI driver -- it may be a red herring but at least it's worth eliminating..

Thank you very much Joe! Information helped me to get my midi controller to work.