Hi Maurizio Domba,

Thanks for reply. Just as you mentioned, both of the users were entering the same unique key. I have added some extra checking functions to prevent this.

Is there any other conditions that may cause the BO.Save() fails and lock the table? I notice that by using Transaction, it will lock the table but not Try and Catch. I would like to prevent any table locking when BO.Save() fails and make the whole application hangs.

Any advice would be greatly appreciated, thanks.