I recently returned from a few days away, and when I came to plug in my iPod the iMac told me that I had "inserted a disc containing no volumes that OS X can read". The iPod still charged but wouldn't show up in iTunes or on the desktop. It then transpired that the same thing happened if I inserted a blank CD in the external CD burner. I tried re-installing OS X from the discs but can't as I get the same message as before, and can't start the installation. Any suggestions would be appreciated. rhinocrat

Okay. It sounds like you have two separate problems here. Let's try tackling them one at a time. First, your iPod problem. If you have your music already on your computer, I would recommend erasing your iPod and putting the iPod software back on the unit. To do this make sure you have the latest OS and iPod Software Updated available to you by first connecting to the internet then clicking the Apple in the top left corner and selecting "Software Update..." in that menu. If you have an older OS (OS X 10.2 or earlier) you can find Software Update in your System Preferences. After you make sure you have these two things, connect your iPod to your computer again then navigate to Macintosh HD- >Applications->Utilities->iPod Software. Within this folder you should have at least one version of the iPod Software Updater. Lauch the latest (they have dates associated with them) version you have and select the "Restore" button once the iPod information appears. This will erase the entire iPod and install the iPod software again. If this utility does not see anything connected you either have some OS problems (which I deal with as part two of your answer) or the iPod or iPod cable have become defective. If your unit is still under warranty you can go to http://depot.info.apple.com/ipod/ to request a box to ship your iPod into the Apple Service Center. Second, your OS/external drive problem. First, I would create a new user by going to System Preferences then selecting the Users option normally in the bottom left corner. There click the '+' button below the listed user(s) to input information for a new user. Log in as that user and see if the external optical drive will or will not read disks. If it does read disks you know there's something wrong with your users folder on the other account and will take some different steps (normall just deleting of the file in Macintosh HD->Users->My User->Library- >Preferences associated with the external drive) but be careful in here. If the drive does not work that means the OS itself is at fault here and you need to reinstall your OS. This is not as hard as it seems and there is an option that will reinstall your entire OS while leaving your Users folder alone. Find your OS disks and place the first one in your optical drive. Restart the computer and hold the 'C' key down. This will start the computer from the CD rather than the internal hard drive. Follow the screen prompts until you reach a screen that has you select your hard drive as your destination volume you would like to install to. There should be an "options" button in the lower left corner. Click that. There will be three options and you want to select "Archive and Install" as well as the sub box that says "Preserve User Settings and Accounts". Keep going from there and it will reinstall your OS. Good luck!