Why should I avoid CatchAll?
A CatchAll mailbox (also called a multiple mailbox) accepts emails sent to all email addresses of a domain for which no mailbox or redirection exists. This can be useful, for example, to catch typos in the email address. Many companies want to ensure that all emails from their customers or potential customers, including those with typos, are received.
The disadvantage: the fact that all emails of a domain are accepted and delivered increases on one hand the general load on the server, and on the other hand the number of successfully delivered spam emails, when spammers send their emails to random email addresses of your domain.
The presumed senders are also affected by this, because the sender information in spam emails is usually forged and spammers use invented sender addresses based on really existing domains for sending. When a spam email is rejected by the receiving server, a non-delivery message is always sent to the presumed sender. As a result, bounces such as error messages from mail servers clutter the mailboxes of the alleged senders. In extreme cases, the number of bounces received in one day can reach hundreds of thousands and paralyze a mail server.
If a Catch-all account is configured for the domain concerned, both spam and bounces, which would normally go to a non-existent email address, are no longer rejected, but are redirected to the address registered there. However, this address is often not on the hosting.fr mail server, but with an external mail provider, which results in spam reception by the hosting.fr mail server. This can cause hosting.fr mail servers to end up on blacklists through no fault of their own, which subsequently impacts all hosting.fr customers. For the individual customer, this also means that the email address to which the spam was sent also becomes “more valuable” for spam distributors, because the spam was accepted and delivered by the server.
As an alternative to the CatchAll mailbox, we recommend creating the necessary email redirection addresses. In most hosting.fr web hosting packages, internal redirections (= within the same domain) are available without limit and free of charge.