I need to create a workflow rule on the opportunities of our CRM. The idea is that once you create or edit a opportunity, send an alert via email. The theme is that we do not know how to configure the rule criteria to take the modification date parameter  and send the alert to the 10 days. 

Any recommendation will be welcome!

Esteban Elias
Preventa Tecnica - Educacion
Xpears.com