ACP>>General>>Client Communication>Email Settings>>
E-mail package size:
This is the number of maximum e-mails sent out in one package. This setting is applied to the internal message queue; set this value to 0 if you have problems with non-delivered notification e-mails.
Try setting this to Zero.
Unfortunately its not that
I did have a package size of 50, changed it to 0 but no joy...
I tried switching over to SMTP but no joy either....
Any other troubleshooting suggestions??