One of the most common reasons for a Greenhouse user to not receive any emails from Greenhouse is because their email address has ended up on the bounce list. Our email provider, Mailgun, will put an email address on the bounce list if they have trouble delivering to the email address.
The reasons for why emails end up on the bounce list vary so there is not one blanket answer. One of the reasons would be if an email, such as the invitation to Greenhouse email, has been sent to an email address before that inbox was set up and therefore, not delivered. This will cause Mailgun to add that email address to the bounce list to prevent abuse and to protect your Sender Score.
If you believe this is an issue you are experiencing, please fill out the form at www.greenhouse.io/asksupport or chat in. We will be able to verify if this is the case and remove the email from the bounce list for you.