Email can bounce for many reasons. Some of the most common reasons include: the recipient's email address was not spelled correctly, the recipient's email address does not exist, there may be a problem with the recipient's mail server, you may be blocked from sending messages to the recipient's mail server, etc. The specific reason for the delivery failure can be found in the body of the failure notice that you receive. For additional assistance with an email failure notice, please contact our Technical Support Department at (800) 281-3564 to speak with a technician. To aid the technician in assisting you, please have the failure message open when you call.