davmerit

This is could be due to a JavaScript conflict with either your current WordPress theme or one of the other plugins you are using – see Contact Form 7 Email Issues – there is a link there that covers JavaScript Conflicts.

I tested your form at the link provided. It seems everything works fine. I uploaded a .pdf file and I got the green success message.

Did you upload the required file extension in your test?​​

Please include a link to your Contact Form 7 form. If others here are able to understand your actual problem, they may be able and willing to offer a possible solution.

Green box with successful message but no mail to be received, on each address

The green Success message and not receiving any error messages is a very clear indication that CF7 is sending the email.

So your email is probably being seen as spam somewhere in the email process. This is usually due to email headers (in particular the From email address used) or email content.

Emails can be considered spam for a whole host of reasons and get rejected at many points in the email process in addition to your spam folder.

See Contact Form 7 Email Issues – this links to a much more comprehensive article which also covers emails being considered spam.

See also Best Practice to Set Up Mail.

If you find you need more detailed advice, after reading and working through the above links, please include a link to your Contact Form 7 form plus all your input in the Form and Mail sections of the CF7 interface. This should allow others to understand your actual problem and offer a possible solution.

You can add any HTML you want, including any standard HTML form elements, in the form section of the CF7 interface.

In your case you could add something like:
<input type="hidden" name="my-hidden" value="hidden-value">

Where do I go to specify what email the contact form should go to after submission?

You can change this at the Mail section of the CF7 user interface. Add your email at the To: field.

Also, I’m getting the orange box after I submit a test.

See Contact Form 7 Email Issues. There is a link at the bottom of the page to a comprehensive and detailed article which covers many issues. Most people that work through this information appear to be able to resolve their email sending & receiving issues.

This is not available directly in Contact Form 7. It can be done via custom programing but you would need to be rather skilled at WordPress development using PHP and/or jQuery.