I\'m learning Entity Framework under VC# 2010.
I have created a simple table for learning purposes, one of the fields is \"id\" type integer, identity set to true. I
Check in your EDMX model, that the autoincrement field's StoreGeneratedPattern attribute is set to "Identity". In this way, EF knows that the autonumbers are handled by the DB.
Here this is explained better: Autonumber with Entity Framework