How does a file "become" corrupted?

[spyder003]

I have this game (C&C Generals) that I can't get to install. When the installation gets to around 83% it has a problem with one of the files, Textures.big. It says the file cannot be read, and asks me to verify that the file exists and I can access it. I click retry and I keep getting the same message so I have to cancel the installation. I have tried manually extracting the file to the installation folder and that doesn't work either. The file is 333MB, but during the installation or extraction it only opens 42MB and crashes. I haven't had this game installed in about 6 months or so. How could this file just "become" corrupted? It's always worked fine before. The CD isn't scratched. It hasn't been exposed to any extreme conditions, cold, heat, direct sunlight, gamma rays, X rays, micro waves, nothing. It just doesn't work now. I emailed EA tech support and they're supposed to have an answer to me within 24 hours. I have a feeling they're just going to tell me to send the game in for a replacement.

Does anyone know how a file could become corrupted on a CD like this?

[Statica]

Could be a defective CD media itself. As long as EA sends you a replacement CD you're set.

[Heon2574]

What about the CD drive itself? Try another computer and extract the file in question.

[spyder003]

I tried both of my optical drives, same result.

[MaLfUnCtIoN]

i had a very similar problem with bf42. turned out to be a damaged disc. you sure yours isnt scratched? you'd be surprised how some minute scratches can cause failure but the big ones seem to cause no problem.

[RenamonXP]

Yeh I've had some insanely weird things happen to me that were scratch related.. usually some small scratch that caused it to load improperly or something to that effect.