Hi all, We are an ISP; one of our Client is using our SMTP server as a Relay Server. Problem is that after some time one of our client is complaining that when they Email their All Staff, the mail did not receive to all of the recipients and it returns back from our mailing server. On our mailing server we tick on the 'Limit Number of Recipients per message to 64000' and in the Global Settings we click on the 'Number of Maximum Recipients' to No Limit. They are using our SMTP server to email from their branch office to Head Office or any where else. Error message Your message did not reach some or all of the intended recipients. Subject: Test Message Sent: 6/23/2005 10:18 AM The following recipient(s) could not be reached: 'salmanlatif@xxxxxxxxxxxxxx' on 6/23/2005 10:19 AM There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. <mail1.multinet.com.pk #5.5.0 smtp;501 maximum recipient count exceeded> Kindly do reply any suggestions, solutions. Regards, Farhan