Configure IMAP for SBS2003

Hi Experts

I am having difficulty getting a mobile device to send email via my SBS 2003 server.  I have the port 143 forwarded from my router to the SBS server and the user has a valid account.  He can connected and download folders and messages to the phone he is using.  However, when he tries to send the device gets an error message:

The message(s) could not be sent.  Check that you have network coverage and that your account information is correct.  Then try sending again.

Firstly, the network coverage must be okay as he was able to download incoming messages only seconds before and the username and password must also be okay for the same reason.

Thanks in advance
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Dave StringfellowIT managerCommented:
It depends on the network you are using. Some Phone Providers block port 25 unless its to their mailservers, talk to them about if they have a mail server you can sent via.

Make sure port 25 is open to your server if your ISP isnt blocking it on the phone, and make sure the device is logging on to the server with a username/pass or it will be blocked.

What device are you using? most now come with Activesync and is a much better way to send mail rather than IMAP.

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