quote:Hi,If Squirrelmail does not send mails to other email boxes then follow these 2 steps: Comment the following 2 lines in your sendmail configuration file whose path is /etc/mail/sendmail.cf and restart your sendmail with the command /etc/init.d/sendmail restartR$*%$*<@> $#error $@ 5.7.1 $: 551 We do not relayR$*<@$+>$* $#error $@ 5.7.1 $: 551 we do not relayNote: The commented lines are as follows:#R$*%$*<@> $#error $@ 5.7.1 $: 551 We do not relay#R$*<@$+>$* $#error $@ 5.7.1 $: 551 we do not relayRegards,---------------Asif BhattiTechnical Support EngineerHostingController.com