Problem with mail from website

Hello,

Excuse, my poor english, i’m french.
I have a problem with the mail send by my website.
The others mail send mannually are ok but MP notification, or new topic notification doesn’t pass.
I think it’s because localdomain but i don’t know how to change that.
Here is a paste of the error mail that i receive : (thanks for your help)

This is the mail system at host sd-29675.localdomain.

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

guillaume.paret@laposte.net: host smtp4.laposte.net[193.25.21.13]
said: 501 5.1.0 Emetteur invalide. Invalid Sender. LPN007_405 [405] (in
reply to MAIL FROM command)

Reporting-MTA: dns; sd-29675.localdomain
X-Postfix-Queue-ID: 75F6A1C4159C
X-Postfix-Sender: rfc822; foruigarette@sd-29675.localdomain
Arrival-Date: Fri, 14 Oct 2011 13:43:47 +0200 (CEST)

Final-Recipient: rfc822; guillaume.pailt@laposte.net
Action: failed
Status: 5.1.0
Remote-MTA: dns; smtp4.laposte.net
Diagnostic-Code: smtp; 501 5.1.0 Emetteur invalide. Invalid Sender. LPN007_405
[405]

Return-Path: forum-ecigarette@sd-29675.localdomain
Received: by sd-29675.localdomain (Postfix, from userid 1001)
id 75F6A1C4159C; Fri, 14 Oct 2011 13:43:47 +0200 (CEST)
To: =?UTF-8?B?cGFpbHBvZQ==?= guillaume.paeret@laposte.net
Subject: =?UTF-8?B?Tm90aWZpY2F0aW9uIGRlIHLDqXBvbnNlIMOgIHVuIHN1amV0IC0gVUxUSUJP?= =?UTF-8?B?WCA6IFBjYiBkZSBnZXN0aW9uIHBvdXIgYm94IGJvb3N0IGxjZCwuLi4=?=
X-PHP-Originating-Script: 1001:functions_messenger.php
From: forumecette@forumcigarette.com
Reply-To: forugarette@for-ecigarette.com
Sender: forcigarette@fo-ecigarette.com
MIME-Version: 1.0
Message-ID: db1b3a1d9660410962e069c16c260189@www.forum-ecigarette.com
Date: Fri, 14 Oct 2011 13:42:24 +0200
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: phpBB3
X-MimeOLE: phpBB3
X-phpBB-Origin: phpbb://www.forum-ecigarette.com

Bonjour ,

Vous recevez cet e-mail car vous surveillez le sujet, “ULTIBOX : Pcb de
gestion pour box boost lcd,…” sur “FORUM-ECIGARETTE Le repaire des
vapoteurs”. Ce sujet a reçu une réponse depuis votre dernière visite. Vous
ne recevrez plus aucune autre notification jusqu’Ã votre prochaine visite
sur le sujet.

Pour voir les nouvelles réponses, cliquez sur le lien suivant:

http://www.forum-ecigarette.com/viewtopic.php?f=492&87

Pour voir le sujet dans son ensemble, cliquez sur le lien suivant:

http://www.forum-ecigarette.com/vos-creations-de-mods-f492/ultibox-pcb-de-gestion-pour-box-boost-lcd-t31219.html

Pour visiter le forum, cliquez sur le lien suivant:
http://www.forum-ecigarette.com/vos-creations-de-mods-f492/

Si vous ne voulez plus surveiller ce sujet, vous pouvez soit cliquer sur le
lien “Arrêter de surveiller ce sujet” en bas du sujet ci-dessus, soit
cliquer sur le lien suivant:

http://www.forum-ecigarette.com/viewtopic.php?uid=4915&f=&unwatch=topic

It sounds like your hostname may not be set correctly… you’ll want to set your hostname to be an FQDN, in the format “host.domain.tld”.

You can do that by running “hostname host.domain.tld”, and then restart Postfix.

-Eric

thanks
i’ll test that.
When you say hostname host.domain.tld it’s better to me to put sd-29675.dedibox.fr or forum-ecigarette.com ?

You would want something in the “host.domain.tld” format, so that would be like "sd-29675.dedibox.fr ".

-Eric

thanks you very much