Symptom
After installing Carbon software, you are unable to stop the Classic environment, shut down, or restart the computer by the normal commands.
Note: "Carbon" is a type of Mac OS-compatible application that has the potential to work in either Mac OS 9 or Mac OS X, depending on circumstances. If you are not sure about what type of software you have, take the precaution listed below.
Solution
Upgrade to Mac OS X 10.2 to avoid this issue.
If you have not yet installed software on an affected version of Mac OS X (10.1.5 or earlier), then avoid the issue by simply stopping the Classic environment before you install software. To stop Classic:
1. Save any files open in Classic, if necessary.
2. Choose System Preferences from the Apple menu.
3. Choose Classic from the View menu.
4. Click Stop.
Note: This procedure is especially important if the Carbon software you are installing does not require you to restart, because the issue will not appear until the computer is restarted or shut down (or Classic is stopped), which may be at a much later date.
If you have already installed Carbon software on an affected version of Mac OS X with Classic running, you may force quit Classic:
1. Press the Option-Apple-Escape key combination to open the Force Quit Applications dialog.
2. Select Classic Environment.
3. Click Force Quit.
4. Verify that the Carbon software was installed correctly, reinstalling if necessary.
5. Start Classic again.