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Bounces & Spam

Read here what can cause an email to receive a soft or hard bounce

Updated over a week ago


When an email is ‘bounced’, it means it cannot be delivered. There are two types of bounces: a hard bounce and a soft bounce. The type of bounce indicates the reason why an email is not accepted:

  • A soft bounce means that the email address is correct, but the inbox of the recipient is full or a mail client that is temporarily not working properly.

  • A hard bounce means that the e-mail address does not exist (anymore) or the domain name has been blocked. In case of a hard bounce, your email will never reach the recipient.

  • 'Blocked' emails are similar to what you call a 'soft bounce'; the receiving server temporarily rejects incoming email. This is a non-permanent rejection for the incoming email. It's a rejection of the message and not an indication of the quality of the email address being sent to. In this case, you can contact Momice and specify which email addresses are affected, we will check them for you with the mail server. With 80% of the blocked e-mail addresses, it is the case that they have previously had the status "soft" or "hard" bounce and the mail server blocks the transmission for security reasons. This is to protect the mail server. When it continues to mail to (temporarily) blocked e-mail addresses, it is harmful.

  • A ‘rejected’ email cannot be delivered due to an error or typo in the email address.

  • A ‘deferred’ email cannot be delivered temporarily, due to unknown reasons.

  • Unsubscribed: some web mails like Gmail or Outlook offer the possibility to unsubscribe with one click by adding a link at the top of the mail.

Mail statuses

  • Delivered: the mail was sent properly from Momice. In most cases, the mail will have arrived in the inbox, spam or junk folder. In some cases the mail may not have been received properly, this depends on the mail client.

  • Opened: the mail has been opened several times by the invitee in the inbox.

  • Unique-opened: the mail has been opened 1 time by the invitee in the inbox.

  • Clicked: a button or hyperlink has been clicked in the mail.


There are several reasons why an email ends up the spam folder. Every receiving party has their own rules. Sometimes, a company indicates a limit to the amount of emails that can be received from a specific sender - or only allows senders that are 'white listed' (allowed). Unfortunately, the policy is not transparent and we cannot prevent emails from ending up in the spam folder.

Momice has made technical arrangements with multiple parties, in order to make sure that emails are delivered. Keep a close eye on your soft bounces and contact us when you suspect that your emails are not delivered.

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