CF7 Sendgrid

Hello,

Thank you for your excellent plugin! We are trying to configure our wordpress site to use CF7 along with Sendgrid and the two do not seem to want to play nice together. Have others reported this same issue?

What I’ve tried so far:
1. Sendgrid sends the email fine alone
2. The WP-Sendgrid plugins test feature works fine http://wordpress.org/plugins/wp-sendgrid/
3. The “Check Email” plugin works fine http://wordpress.org/plugins/check-email/

However, when I go to my site’s front end (http://www.openletter2013.org/send-the-letter/) to use the form itseld, it gives me an error. I made sure to differientiate the error message from the spam message, so I know it is indeed a failure to send. Does this plugin use the built-in wp_mail feature or something else?

Any suggestions?

http://wordpress.org/extend/plugins/contact-form-7/