There are several reasons why an email may not deliver to an email address. If an email fails to deliver, you will be notified in the 'Email Delivery Issues' box in the notification centre.
The most common reason is that the customer has entered an incorrect email address (see if there are any obvious typo’s or spelling mistakes) and the customer should be contacted by phone for the correct email address.
It may filter into Spam - in this case you will need to ask the customer to mark you as safe.
Their inbox maybe full
For corporate clients, quite often they have very strong spam filters and so the email will not deliver. Again, the customer should be contacted via phone to reach them at a personal address. Or ask them to mark your address as safe and then resend the email.
Sometimes an email might not deliver to a customer straight away but may be deferred. Here is what Mandrill, our transactional email platform, say on deferred emails:
“We do everything we can to deliver messages within seconds, but sometimes we run into roadblocks. The recipient's account might be over quota (even in the days of multi-gigabyte quotas, that still happens!), or the receiving server might be experiencing some other general problem. In cases like this, there's nothing we can do to make the message send more quickly, so we queue it and retry automatically.”
If Collins is unable to send a new message you will see various notifications.
The red exclamation mark next to the messages tab will display if there are any unread email delivery failed notifications against a booking.
There will also be a red exclamation mark in the messages section, left of the subject, against any booking that has failed to send.
There will also be an explanation as to why the message was unable to deliver. There are several reasons that an email may not deliver:
Attachments are too large
The email provider was unavailable at the time of trying to send (General mailer error)
There will also be blue open envelope for any outbound emails that have been opened by any recipient.
If any message fails to send you will be notified in the Email Delivery Issues section of the notification centre. To find all those bookings with email issues, you can use the filter options ‘Notifications > Email Delivery Failed’