PostFix Delivery Problem (Hostname related ?)

Hello,

I changed the hostname of my VirtualMin (latest version, installed through install.sh) server using "hostname" linux command. I also noticed a "myhostname" line in "/etc/postfix/main.cf" and updated it accordingly.

From now on, I can't send email to addresses of any virtual servers.

The error I got :

user.domain_without_tld@sd-XXXX.dedibox.fr (expanded from user@domain.tld): mail for sd-XXXXX.dedibox.fr loops back to myself

(actually the "domain_without_tld" is the Unix username of the main account for the virtual server)

I checked for topics on the forum but everything "seems" fine regarding those topics.

Par of my "main.cf" file:

alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
mydestination = localhost, localhost.fr, localhost
relayhost = 
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_command = /usr/bin/procmail-wrapper -o -a $DOMAIN -d $LOGNAME
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
virtual_alias_maps = hash:/etc/postfix/virtual
sender_bcc_maps = hash:/etc/postfix/bcc
home_mailbox = Maildir/
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions = permit_mynetworks permit_sasl_authenticated reject_unauth_destination

The line "mydestination" seems different from ones I found on some topics but I never changed this file and topics are a bit outdated.

My "/etc/postfix/virtual" file also contains lines such :

domain.tld domain.tld
user@domain.tld user.domain_without_tld

I left the default option of "user.domain" for login.

Thanks in advance.

Tristan