The error message that you are receiving is a generic error message (not necessarily a disc related problem) that indicates the game is unable to retrieve the specified file. This is most likely due to the file being corrupted during the download or installation process, but may also be the result of a bad sector on the hard drive. Try the following:
1. Check the size of the game installation (write it down). Uninstall the game. Eject the disc if you have the disc version.
2. Restart the console
3. Download a demo or several demos that are as large in total size as the game installation and DLC
4. Now install the game and DLC and try the game again.
If possible, use a wired connection when downloading content. You may also want to connect directly to the modem.