Originally posted by: corkyg
Can't you just copy the CD to a folder on your HDD and then designate it as the CD in the game? I do that with a couple of programs that require a data CD in the drive - just because it is faster.
The problem lies in how manufacturers create their CDs. They manipulate how CD reading occurs to prevent illegal copying of their software.
Sectors on a CD are numbered in increasing order (e.g., 123, 124, 125, 126). When reading from a CD, it tracks either forward or backward to the sector based on which sector it is currently scanning (e.g., from 123 to 125, it passes through 124, but from 126, it doesn't). Many manufacturers take advantage of this and add a bad sector intentionally, then scan from ahead of the bad sector (e.g., 123, 124, 124, 125, 126. They would scan from 126 or so). The CD would pick up the data in the bad sector, and then you know that it's a valid CD. Burned CDs usually don't pick up on the bad sectors, so they don't work with the game.