I get duplicate emails...why?

If you start to recieve many copies of the same email (particulary large emails) then you may have a timeout problem with your qmail server.

This is caused by your server not sending a "250 OK" message back to the remote server after accepting the email. This can happen if your server timeouts after accepting the email.

We have ssen this several time where the customer has installed filtering software and incorporated it into the server incorrectly.

If you see this happen we suggest that you have a look at the filltering software (spam / virus etc) is installed correctly.