Me too! I've been on it for 2 days now. I tried everything. Tinyumbrella, data recovery, recover using download ipsw...etc. This happened when I tried to upgrade a jailbroken Iphone 4 from Ios 5 to Ios 7. Right now i'm trying recovery downgrade to Ios 6.3 using tinyumbrella. Anything just to get out of the recovery mode loop. Please lemme know if you figured a way out! Thanks.