confirm a new purchase order

Hi every body,

I set a new AX 2012

and after the creation of an order (purchase ordre), I can not confirm the tab: purchase, the icon (confirm) is gray!

My friend has set the finances and we set up together a workflow for the submission, but there is nothing!

The icon is grey ! 

Réquisition orders are grey too ?? 

is there a spécific action to do during configuration of a new AX 2012 R2?

Thank's in advance

Zoheir.