Contact Form 7 not sending mail

I am using CF7 4.8 in a Cherry framework, Monstroid2 theme. Email for my domain has been set up and verified. I have created an email account for me. I verified with the latest version of the Check Email plugin that my WP installation will send email to wherever I want, including my email account on my domain. (I am using php mail, not SMTP.) I have created a very generic contact form and a page to load it. However, whenever I attempt to use it to send a message, it always comes back with “There was an error trying to send your message. Please try again later.” I contacted InMotion and they told me many of their users use CF7 and it works fine for them. He could not find any email problems on their end. Mail tab is set up as follows: (mydomain.com is a pseudo-name for privacy purposes here. I actually use my real domain name.) To: [email protected] From: [your-name] Additional Headers: Reply-To: [your-email] I am not using Mail (2). Where do I go from here?