Admin why can't I send email when I am connected to a wifi network connected via Wi-Fi? it works great via edge (but slow!!!)
Here is the solution set your outgoing servers SMTP to be Gmail:
If you are like me and noticed that not all your emails were being sent when you were on a wi-fi network because of SMTP server settings for local networks, or you noticed that emails set to send via AT&T's SMTP server would only send when connected to the EDGE network (or you're paranoid about sending email via AT&T servers), you can use Gmail as your master SMTP server that will work over both Edge and wi-fi.
I noticed this issue when setting up my work email with the iPhone. My work email only uses the local SMTP of our ISP. My immediate solution was to use AT&T's SMTP server cwmx.com. But I noticed that this would only send if I was solely on the EDGE network. So if I were at home and I was connected to my wi-fi, I would have to turn off my wi-fi on the iPhone and get on the EDGE network to respond to a work email. I found this annoying.
My solution was to use Gmail's SMTP server with an account that I have there, and then use Gmail to spoof my return address so that the emails would appear to come from my work address. [MacOsXHints]
