whats ios version on phone?
if its not 7.0.1 then you can forcely factory resetting ...
plug phone to your itune... (does not matter its recoganize or not)
hold power button and home button togther until phone got power off and come back on..
release Power button when Apple logo comes...
contine hold Home button...
and you will see iTune see phone connected...
release the home button and and follow instruction on itune to restore iphone...
(make sure you have latest version of iTune and All windows or mac OS updates/patches)
& you will be done..
if you failed to do so... make sure you updates your Mac or Windows system Updates...
let me know its works for you or not.. because i had same issue and i fixed it... that way
thanks for your time