Cd-r disc

Hello,
I have been putting data on a CD-R disk since 2008 and all of a sudden it won't read in my computer. Nothing will come up. I have been viewing this data for months so I know there's something on it. And by the same token, the CD player plays all the other disks that I use which leads me to believe it's not the computer. Any input you have on this problem will be greatly appreciated. The disk is a intricate part of my job.
Configuration: Windows Vista Internet Explorer 8