I get an error message saying: The File Couldn't Be Opened either when clicking on the New Project button, an old file or in Magic Garageband the Open in Garageband button. I already tried one suggestion on the web about deleting the plist and letting Garageband recreate it, but that didn't work. I didn't see this topic in the threads so hope it's not already covered elsewhere. Have not been using Garageband since I upgraded to iLife 11 so didn't realize there was a problem till now. Just got a USB mic and this is the only program I have to use it with. The audio project I wish to work on will have to wait till I can get this solved. Thank you in advance for everyone's help.
+I or go to File->Get Info. Under the Sharing and Permissions section, open the lock in the bottom right and authenticate using the admin password. Next to your user shortname select Read & Write, then click the gear icon and choose to "Apply to enclosed items". Wait for the process to complete before trying to relaunch GarageBand.