Disable spam protection?

I’m using Contact Form 7 for sign up for seminars.

I recieve most of the sign ups without problems, but a few times i’m contacted by customers who are getting the “There was an error trying to send your message. Please try again later” with the orange box. I’m almost sure that all of the problems came from customers with .com e-mail addresses.

The customers e-mail address is only used in the content of the e-mail sent to me on submission. It’s not used in the “From”-field.

I suspect that Contact Form 7 has some kind of spam protection (nonce?) that sometimes is a little too aggressive.

Is it possible to disable the build in spam protection, or perhapse turn down the aggressiveness?

I would rather manually delete 10.000 spam e-mails than miss a single sign up for at seminar.

Thomas

https://wordpress.org/plugins/contact-form-7/