i find that when I create and send an email. it creates and sends two copies of the same email. How do I make this stop?

problem sending emails

Are the recipients getting two copies, or is it just two copies showing up in your Sent folder?

I am not sure. _ I just sent an email to another of my addresses.  it shows only 1 sent, and  _I received only 1

Maybe it was some glitch on the server and is now working as it should. It can happen that after the message is sent, the server does not confirm the send, and so the client sends it again. 

thanks!  I will monitor.