i just send 5 e-mail to an address using the outlook express,then i click on the sent items,all the 5 e-mails are shown there.

But my AVG program seems to be scanning the message and sending it again leh..

then i received an e-mail as below

This is the AVG E-mail Scanner program.

I'm sorry to have to inform you that the message returned
below could not be delivered to one or more destinations.

Receive: : The operation completed successfully. (0)

Your e-mail message is being returned to you in the next part of this
message. Try to send the message again.

Should you need assistance, please contact your administrator or your
internet service provider.

What does it mean ?

Are my 5 e-mails sent ??