Do you know anyone else with an xbox, that is willing to let you barrow their hard-drive? Doesn't matter if their box was modded or not. You need to boot up their HDD, and copy the stuff on it with evoX. I know a way that might work, but you need to barrow some1's HDD. Also, you may need to purchase another HDD ($40 or so for a samll one, a little larger than the xbox hdd).
OK, this first method might not work, and I dunno what will happen if it doesn't. You switch HDD's with someone else's xbox. Power on and load up evolutionX.
Then connect to evoX with FlashFXP and copy the C drive. Shut-off your xbox and quit flashFXP.
Next, boot up you xbox and load evoX again. Then (this part, im not sure what will happen) Switch HDD's while still powered on and THEN connect to your xbox with FlashFXP. This will connect to your F'ed up HDD.
Then you send the C drive (that you copied) and overwrite the messed up files.
Note: I dunno if you can switch HDD's while still powered on. You have to do this if you do the HDD mod so I'm only assuming it works.
This is the second method. You also need to barrow someone elses xbox HDD. You switch it with yours and boot up. Then you do the HDD mod found
here. You will need to buy another HDD to replace the old one.