Try pressing the F12 key when the Toshiba script shows on the display. You should see either a list of boot devices to select from or some Icons to choose from. If you have Icons, use the right and left arrow keys to select the CD and then press the Enter key. If this method doesn't work you will need to change the boot sequence in the BIOS. To enter the BIOS, press the Esc key when the Toshiba script shows up on the display. You should then get a message to press the F1 key to continue. Press the F1 key and you should be in the BIOS. The Boot sequence is on Page 2 of the Bios settings on many Toshibas. To get to page 2 press the page down key. Make sure you follow the screen prompts because your system may be slightly different.