If you replaced batteries with known good ones then the only thing that could have gone bad is the capacitor that loads up and fires the flash. Carefully discharge whatever is left in it , remove and replace. Should do the trick.
GT Recovery for Windows Download: www.gtrecovery.net
GT Recovery for Windows is a professional data recovery for Computer and Android phones. It can restore deleted photos, videos, audios, documents from Andorid phones. Whenever you lost important photos or deleted photos by accident, you can use it to scan and recover the photos on your phone.