Contact Form 7 Mail Issue

Cannot find any forums topics that answer my question, but basically my issue is this:

I am trying to set the FROM field in the mail section of my “Contact Us” form and it tells me the email needs to be from the domain…but by nature the person visiting the site and sending us a message via the contact page is NOT from the domain. Can anyone explain better how to properly write the syntax in the From field for the mail tab so that a visiting guest can send an email to us, the employer, when they submit a contact request?