CD-ROM drive is not the D: drive.

Cause:

Another drive or partition has been added to the computer.

Solution:

When another peripheral is installed into the computer, the CD-ROM will automatically be defaulted as the last drive in Microsoft operating systems. For example, if your CD-ROM, DVD or other disc drive was the D: drive and you've added a new hard drive to the computer your disc drive will now be the E: drive.