As far as I remember the Buffer I/O error on a CD-drive implies that the drive is not able to read the disc, maxing out the buffer and thereby causing this stop error. The reasons for why you are getting this error can wary from a actual hardware problem with the CD-drive to a corrupt CD. I would advice you to first of all re-burn the CD, at a low speed, and check if it solves your problems. Unless that helps, chanses are that you will have to get yourself a new CD-drive.
Also the fact that you have not made any significant changes in windows recently is in no way relevant, unless you have upgraded the actual firmware on the CD-drive.



