Sir. You have to provide more specific information. Phone type, rom version before issue, rom version you tried to update to.
There are many possible causes and solutions. For the average user if you can't get kies to help then getting a warranty repair would be best. However, one simple solution which usually works is to. Flash a stock rom* in odin. Then, if it doesn't boot, go to recovery and wipe data / factory reset. If that doesn't work then you may want to research using a pit file
If you haven't read prepare to be ignored, or worse.