To set up email poller in Appian, can we use Windows authentication to read the

I do not think the current mdb allows for WIA. Please submit an enhancement request.
Also, what are you using emails for? Are you reading system-to-system emails or end user ones? If system-to-system, look into more reliable interfaces like web services or JMS.

It is for end users to send emails to kick off Appian processes.

Can you allow users to login to Appian and kick off processes as actions?

It will give you more control over the information that comes through, otherwise user emails are notoriously hard to parse and you will have to have a person validate the data that came through.

Does this windows authentication have rights to read emails from specified account , If so you can add in it.