If you want to export data to a table which has identity column or you want to import data to such a table in management studio 2005 you should consider a precise point. First you should check "Enable identity insert" in advanced settings, but if you select "optimize for many tables" too, then the identity values for the destination table are renumbered and identity insert does not work as you expect. The cause of this problem is that "Optimize for Many Tables" creates a SSIS package which transfers the tables one-at-a-time within a For...Each looping structure and it does not include the logic to enable identity insert, so you should disable "optimize for many tables" when you have checked "Enable identity insert" option.
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