Cannot Save Game Data
If you are unable to save game data to your hard drive, it is most likely out of memory. Delete unnecessary files from the drive or buy another hard drive or a memory unit if you want to keep all the files you already have. You may also copy files from your hard drive to another hard drive or memory unit and then subsequently delete them from the source drive.
Hard Drive Not Recognized
If the hard drive is not listed among the available storage devices when you try to play a game, it may not be fully inserted into the console. Make sure you fit it on the top and push down until you hear a click. You can also try removing the hard drive and reattaching it. First, turn the console off, press the tab at the front of the hard drive and lift it from the console. Do not touch the hard drive bay contacts and connector contacts with your fingers or other metal objects. To reattach, position the drive over the bay and press it down onto the top of the console. Turn the Xbox 360 system back on and see if the hard drive is now recognized.
Hard Drive Damage
Be careful to keep the drive away from liquids and extreme heat. These can damage the hard drive beyond use and prevent it from being recognized by the Xbox 360 console.
Original Content
Some hard drives purchased in stores come with specialized content. Be careful not to delete this content because it cannot be replaced, unlike the content you purchase off the Xbox Live service.
Xbox 360 Support
If you have a problem with the hard drive you cannot solve, try contacting Xbox 360 support at (800) 469-9269 or xbox.com/support.
Do not take your console or accessories to the retail outlet at which you purchased the equipment unless an Xbox 360 customer representative tells you to do so.