mail not delivering through sendmail

All of sudden my dedicated linux reseller are not able to send emails through send mail.

Message not sent. Server replied:
Email delivery error
67 Can't execute command '/usr/sbin/sendmail -i -t

Please help me

HC support has provided me solution for this issue which worked. Thought I should share it with you

quote:

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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 restart

R$*%$*<@> $#error $@ 5.7.1 $: 551 We do not relay
R$*<@$+>$* $#error $@ 5.7.1 $: 551 we do not relay


Note: 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 relay

Regards,
---------------
Asif Bhatti
Technical Support Engineer
HostingController.com

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