This is driving me absolutely barmy.

I'm trying to set up Thunderbird to send and receive from my job's e-mail address. It's got a pretty useful looking thing when you first start it up where it just asks for your e-mail address and password and works out all the settings for itself. BUT - it doesn't.

What happens is it figures out the correct server and port number for outgoing mail (the SMTP server), but then says that the settings it finds for the incoming POP3 server are wrong (even though they match what I've been given), and then it says that my username and password are wrong. Except they're not, because if I then try and send an e-mail in Thunderbird it works, it just can't receive anything.

I'm trying Thunderbird because the same settings in Outlook allowed me to receive mail but not send it. I tried Opera too, but nothing worked there at all.

WHAT THE HELL IS GOING ON.