You use two DataContext instances to retrieve objects from two database tables. After modifying the returned objects, you call the SubmitChanges method on each instance of DataContext. You want changes to both databases to occur in the context of a single distributed transaction.

What should you do?

By default, DataContext updates occur in the context of the ambient transaction, if there is one. To ensure that a new one is created for the scope of the two updates, use a TransactionScope with the TransactionScopeOption set to RequiresNew. Call Complete after the updates to commit changes in this scope.

Embedding calls to the DataContext.GetTable<T> methods within a TransactionScope does not ensure that the updates are transactional.