When you send a newsletter you will experience that an amount of e-mails are not delivered - these are registered as bounces.
There are two types of bounces, soft bounces and hard bounces. A soft bounce is a temporary error while a hard bounce is a permanent error. A bounce may occur for several reasons.
E-mail address with errors - hard bounce If the recipient filled in hootmail.com instead of hotmail.com or yaho.com instead of yahoo.com the e-mail will not be delivered.
The e-mail address has been shut down - hard bounce Some recipients changed e-mail provider, ie. from Hotmail to GMail, and some recipients change jobs. This results in the e-mail address being shut down and the e-mail will be bounced.
Full inbox - soft bounce Many e-mail providers limit the amount of storage you have for e-mails. The storage may be limited to as little as 10 MB which means that it does not take much to fill the inbox. When this happens e-mails will be bounced.
Receiving e-mail server is down - soft bounce Sometimes an e-mail server is down for one reason or the other and in these cases we can not deliver the e-mail.
How we handle bounces
When we start sending your newsletter we try to deliver to all the recipients on the first attempt. Most e-mails will be delivered immediately but some will soft bounce and others will hard bounce.
Hard bounces are immediately registered as a permanent error and are included in the statistics right away. Soft bounces are collected and the e-mail is set aside - after a few minutes we try to deliver the e-mail again, since the recipient might have emptied his inbox and the e-mail server might be running again. If we receive a soft bounce again we set the e-mail aside once again but this time we wait a little longer before sending it again. Over a period of five days we continue to try to deliver the e-mail. If it has not been delivered after five days then we consider the error to be permanent and register a hard bounce.
When we receive a hard bounce we register it in the statistics - this lets you see exactly how many e-mails were not delivered. When the same address has bounced three times it is suspended and we will not try to deliver to the address in the future. This means that your list is continuously cleaned keeping defective address off. When first sending a newsletter via Ubivox you may experience quite a few bounces if you haven't removed bounces from your lists before. After three newsletters the amount of bounces will decline due to defective addresses being removed and your bounce rate should stabilize at a few percent.
If you send a newsletter to a recipient who we have registered a bounce with before but has not given enough bounces to be suspended, and the newsletter is delivered, then we will reset the bounce count for the recipient as to keep him/her from being suspended, if we receive a bounce at a later stage.
On the statistics page you can download a list of all bounces and the export function lets you download a list of all suspended recipients.