iTunes uses a third party component from GEAR Software for accessing the CD/DVD drives in Windows computers.  This component is registered as a filter driver for all CD/DVD drives.  Sometimes the iTunes installation or upgrade process can cause this component to not be registered correctly, or perhaps even install the wrong version of this driver filter.

There have been many reported problems caused by issues with this filter driver.  Some of these are:
- Inability to burn CDs in iTunes
- Inability to copy songs from CDs in iTunes
- Optical drives completely missing from Windows
- Other software unable to burn CDs (Like Nero, Roxio, etc)
- iTunes has a dialog box that opens when you start iTunes that mentions the registry settings are missing

It is possible, in most cases, to manually fix the registry to alleviate this problem.  You can find instructions on manually editing your registry on Apple's support website at: http://support.apple.com/kb/HT2615.  Attempting to fix the problem manually requires technical knowledge of the Windows Registry and does not verify that the correct driver is installed.

While there are known and published means for manually fixing this problem, GEAR Software has provided an installer that will automate the process.  Using the installer from GEAR is a safer solution than attempting to follow the manual process.  Not only will the driver installer fix your registry entry, but it will also make sure the correct driver file is installed for your computer.  It also has the added benefit of providing you with the latest driver which can include bug fixes and performance improvements.  


To get the latest driver update from GEAR you can go to:
http://www.gearsoftware.com/support/drivers.php

On the GEAR download page you will see a section called "Drivers Downloads" toward the bottom of the page.  To download the software you can click the link for your platform.  At the time of this writing there are two options for which driver to download.  Most likely you need the one labeled "Driver_Installer_x86_x64.exe".  The other option is for computers with an Intel Itanium processor which is mostly used in server computers.

After the file has finished downloading, simply run the installer and it will take care of installing the correct version of the driver and registering it in the Windows registry.  While the installer will not require you to reboot your computer, you'll want to do that to make sure all is working well.

Running the installer will allow all drives to function properly under Windows, as well as providing the functionality for iTunes to access the CD/DVD drives.