This guide details the reasons why sending a Newsletter via Infomaniak may be blocked, as well as best practices to prevent these blocks in the future.

Common causes of newsletter blocking

Sending a newsletter can be interrupted in the following cases:

• an excessive number of recipient email addresses are invalid or non-existent, generating a high bounce rate.
• a high rate of spam reports from recipients.

As a mail host and newsletter sending service provider, Infomaniak is required to implement strict mechanisms to combat spam.

Indeed, if Infomaniak's IP addresses or domains are listed on blacklists, this would compromise the deliverability of all emails sent by its customers, including those in compliance, and harm the overall reputation of the service.

Preventing blocks when sending a newsletter

To do this:

• Use only contact lists obtained with explicit consent.
• Prioritize building your lists through double opt-in forms, ensuring active validation of subscribers.
• Regularly clean your contact lists — at least once a year — with specialized services such as NeverBounce, Bounceless, Verifalia or QuickEmailVerification, to remove invalid or inactive addresses.
• Ensure that your emails clearly display your brand or company name, building trust with recipients and transparency in your communications.
• Avoid importing lists from other hosts without first performing a thorough cleaning of these contacts.
• Carefully check the targeting of your campaign to ensure that only relevant and consenting subscribers receive the newsletter.

What to do in case of a sending block?

In case of a block, contact Infomaniak support quickly to diagnose the cause and get assistance to complete the blocked sending.