So you want to transfer your files from one Xbox HD to the other? Sure it's possible. You need to format the corrupted one as FatX using an application on a modded Xbox. Then you can FTP the files from one of the others to your computer, then back to the newly formatted HD. I did something similar but I got a completely new HD (an 80 GB one) for my modded Xbox and used that instead. Check out the site elitegamer posted above for more information.
Note: You can't just format it like a regular HD on your computer. The Xbox uses a different filesystem (FatX) that Windows doesn't recognize. Also, you need to unlock the hard drive your going to format before you do this (if it's a stock HD). Again, check the site posted above.
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