"Normally Samsung android phones are so secure to flash. but you are unlucky and got your phone bricked during flashing,rooting or upgrading.
Here is a good news for You – A developer come up with a software called one-click unbrick for Samsung android phones. this small utility uses ODIN to repair our Samsung phones. almost all Samsung phones with android éclair and above can be repair with this tool (few exceptions – it is working on some Android 1.5 too)
one-click unbrick tool works on windows , Linux and mac also. it have some bugs in windows version but both Linux and mac working fine. don’t get worried about windows version if you are a window user. developers are continuously working on windows version for its stability"