Succes message shows up but mail not sent

I am having a similar issue, and I seem to have narrowed it down an issue with @yahoo.com email addresses. Those addresses don’t come through. Any one know how to fix this issue?

The green success box 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.
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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 Junk.

@jamie – As per the Forum Welcome, please post your own topic.

Posting in an existing topic prevents being able to track issues by topic. Added to which, your problem – despite any similarity in symptoms – is likely to be completely different.

Problem solved, the sender (e-mail address) was a non-existing e-mail adres. Which the e-mail server blokked.