The iMac (Slot loading) computer's disc eject mechanism is electrical instead of mechanical. To eject a CD-ROM disc at startup that contains system software, press the mouse button until the computer ejects the disc. If the disc does not contain system software, wait for the iMac to start up and drag the disc icon to the Trash.
If either of these steps fails to eject the disc, push the drive's manual eject button with a small, blunt object like a paper clip. This button is located to the right of the CD/DVD slot as shown in Figure 1. The computer must be turned on to eject a disc in this manner.
Figure 1 Manual eject button
Once the disc is ejected, it extends just beyond its center hole so you can remove it from the drive. If the disc fails to eject, while holding in the paper clip, use another CD to gently push against the inserted CD. This gentle pressure may help to release the inserted CD.
Important: After ejecting the disc with the manual eject button, you must restart the iMac in order for the CD-ROM or DVD-ROM drive to work.
Note: Because the drive is slot loading, you should insert only round 77 or 120mm discs. The drive does not work with irregularly shaped discs, which could damage the drive if inserted. For images of the unsupported shapes, refer to article 58641: "Macintosh: Using Nonstandard Discs in Optical Media Drives".