Free SMTP server? [SOLVED]

Projects Networking, Protocols, and Devices
1

I have some code that works great with Wifly, Arduino and Gmail.
Unfortunately it gives me this error when I'm using T-Mobile Mifi only.

So I thought I'd try this:

Using this method at the bottom of the page AUTH LOGIN
http://www.petri.co.il/smtp-authentication.htm

There must be an easier way. Unfortunately T-Mobile does not have it's own SMTP relay or server without authentication.
Please help!

2

Do you think this might work without the same error GMail gives me?
smtp.comcast.net

There's only one way to find out!
Unfortunately I have to climb a mountain to test it...

3

You can host your own mail server...

4

Unfortunately my PC does not have an external IP address. Sprint 3G.

5

SMTP2GO seems to work using Sprint. Next try T-Mobile!

6

Thanks for listening! Works with T-Mobile.