Why do contacts receive an email or newsletter multiple times?

OptiOffice wants to send your emails to your recipients. It connects to your mailbox provider via SMTP and the emails are transferred to their SMTP server. From OptiOffice's point of view, this is the end of the matter. It's like putting a stamped letter in the mailbox. After that you can't do anything anymore.

The provider that manages your emails can be, for example, Microsoft Office 365, GMail, Web.de, 1und1 or Ionos. This mailbox provider wants to avoid its servers being used for spam. Therefore, to be on the safe side, a so-called “quota” or sending limit is set by the provider, which only allows a certain number of emails in a certain time frame (minutes/hours/days).

Of course, our server wants to deliver the email reliably to your customer. That's why it sends the email again later after a failed attempt (e.g. due to a limit being exceeded). This is generally the case throughout the SMTP system. If the limit is then open again, both the first email and the new email will go out. This is because some providers' servers buffer these emails, but they do not tell us this. This is why customers sometimes receive emails multiple times.

The solution is simply to book a larger package with your provider that has a higher limit or even no limit at all. So the limit grows with your company.

Here is an example of the limits for Microsoft applications:

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