IPhone 3gs Error #21?

error is
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Long story short;
Tried recovering - Won't work
Update iTunes - Won't Work
Tried multiple methods on youtube stating going in DFU mode and recovering - Won't work
Tried tinyumbrella - Won't work
Edited Hosts like on apple support - Won't work

No idea what's left to try, hoping there's a manual fix rather then having to pay @ a store to fix it.

(ps, the phone is now 2 years old - just extra info)

 

Did you try this method? Worked for me this summer.

http://www.youtube.com/watch?v=_jV6su4qJEw

 

it didn't work ;l

edit: I found that my usb cable had a slash (cut through the plastic) right at the end of the usb side. Tomorrow am going to buy a new cable, maybe it will solve le issue.