Douglas,

>“Concurrency violation: the update command affected 0 records”
>
>I get this error only if one of my child biz objects has broken rules and after filling in the correct field so the rules pass and I click on the save button, i.e. after clicking the save button the second time.
>
>Does anybody have an idea what could be causing this?

Did you set the business object's AutoUseTransactions to true so that changes are rolled back when the save fails?

Regards,