ethernet shield web server and email client

does anyone know if and how you can use this board as a ethernet server then switch over to a client to send a email?
or can you only use as one or the other?

Yes, I have. I believe zoomkat has also. It is easier if you use web client and email, but it is possible with a server.

I recommend testing each in its own sketch before combining them. The email part is the most difficult due to the way you must send it. You can't use SSL or TLS security because the ethernet library does not support either, so it must be accomplished as an email server would send email to another server.

Here is my example code from the playground. Test it first. In any case, whether you use my code or some other example, you must read the response from the email server or there is no way to debug it.
http://playground.arduino.cc/Code/Email
BTW, if you try to send email to my email server without reading the responses, it will refuse your email and the email log entry states it was rejected because the server was "rude".

Yes, my Arduino system operates as a web server publishing pages and receiving inputs AND it also sends me emails when something urgent happens. I use push email on an iPhone so I get system emails within about 20 seconds.

But I cannot remember how I did it - I obviously copied something from standard examples and worked forward from there.

I believe they can operate independently - an EthernetClient object can exist at the same time an email is being sent.

Catweazle NZ