Email NDR reports do not work

[webbit]

When clients email from webmail on my plesk for windows 7.5.5 server to an invalid email address they do not receive a NDR bounce message back to them and hence do not know that a message has failed.

I have tested sending to an address that I know I get NDR reports and confirmed that nothing is ever received by my client.

I have checked the mail enable settings on the server directly and can confirm that both in SMTP and the Postoffice properties all settings are set to Deliver NDR reports.

Please help. I'm sure this is going to be a plesk bug.
Can anyone else confirm or deny that they have this problem.

This was also present in Plesk for Windows 7.5.4

This does not affect Plesk for unix....

Thanks