- 1). Close any programs that are using the CD-ROM.
- 2). Open a terminal window by clicking the Ubuntu logo at the top-left corner of the desktop, typing "Terminal" into the search box that appears at the top of the screen and pressing "Enter."
- 3). Type "sudo mount -o remount,ro /dev/cdrom /mnt/cdrom" into the terminal window, replacing "/mnt/cdrom" with the mount point of your CD-ROM, if it's different, and press "Enter."
- 4). Type your password at the password prompt and press "Enter."
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