Tethering iPhone 4s - Outlook won't send issue

When I am tethered to my iphone 4s, whether it be through the WiFi hotspot or connected with the USB, I am not able to send email from my Outlook 2007. If I connect using a LAN connection at home it sends just fine. Any suggestions?

I have read quite a few posts from others and have not seen any advice for this issue that would fix the problem. Could this be an iPhone problem? My Andriod 2.2 phone does not have this issue when I am Tethered to it.