Messagerie windows mail

Bonjour,
This is the mail system at host msfrf2304.sfr.fr.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

Adresse mail supprimée par la modération: Host or domain name not found. Name service error for
name=**** type=A: Host not found

This is the mail system at host msfrf2304.sfr.fr.

je reçois souvent ce genre de message alors que parfois le message passe qd meme et que l'adresse mail est exacte ou est le probleme MERCI