When sending a Group Mail to customers 300+ receivers, i get a error message about a non valid recipient email address. The mail show's up in my sent Mail folder but has it been sent to the valid address or not ? All recipients were in a single bcc field. My own address was there also but i did not receive the mail, can it be it still went to recipients that were it the receivers list before the invalidi email address ? Really dont want to spam my customers by resending