Hi Yaribel,

as far as I know Nintex can't monitor the new mail event. However you can do so with Microsoft Flow if you're using Exchange Online in Office 365.

Would that be an option for you?

Best regards

Enrico

You can use the When a new email arrives trigger to create a flow that runs when one or more of these email properties match criteria you provide, A good starting point for flow would be : Run flows based on email properties. | Microsoft Flow  

Thanks for your answer, actually we don´t use Exchange Online in Office 365, does it works on Exchange on site?

Ahh... Flow does not work with Exchange on site, Overview of connectors for PowerApps 

Do you have also SharePoint on-premise? Maybe you could approach that the other way round:

1. A rule on Exchange, that pushes each mail to a "site inbox".
2. A workflow (ex. Nintex or even SPD) listening in SharePoint on-premise, for a new email that arrives to the "site inbox". 
3. Once an email arrives, simply call the webservice to execute Nintex Workfow Cloud workflow or a Flow workflow that will do other actions.

But I have no idea about the background and the architecture of your environment, sooo... Can't tell if that is feasible

Regards,

Tomasz