Symptom
Classic unexpectedly quits or issues an alert message during its startup.
Solution
Check the amount of free space available on the disk that contains the Mac OS 9 System Folder. If there is no (or very little) free space, copy or delete files from that disk to create more free space.
Note: Because of differences in the way that Mac OS 9 and Mac OS X use disk space, Mac OS 9 may report that there is space available on the disk when Mac OS X reports that it is full. You will need to ensure that Mac OS X reports free space in order to start the Classic environment.