We are using qmail server in our organization. we are using this server since 4 years. we are facing duplicate mail issue. getting more than 25 duplicate mails for each mail. Please help me out with this issue.
Is this related to email that the server is sending or receiving?
What do the mail logs say?
Is there a process that is timing out such as anti-virus or spam filtering that's taking so long to complete that remote mail servers timeout and resend even though you might have eventually delivered the original message?
Less likely, any recent network changes that might be affecting tcp/ip, or general network issues near the server? Have you checked for a bad network & packet loss?