Documents awaiting for your validation appear under your tasks, if this is not the case (users created or reactivated while documents being already validated) you may retrieve them via the reports objects in the queue, order follow-up, forecast follow-up and standard list search.
Click on the document's reference in order to access to the validation buttons:.
Validation or rejection of an order and forecast is done via the button "validate/reject" situated upper right-hand side of the window. Comments may be added in order to justify the decision, and those will be visible in both the email notification triggered upon validation/rejection and the validation on the actual document.
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