Adding business email to mac mail

Hi All, I have got a business email from crazy domain I have been on the phone with them to try help me get this email address to my Mac, they went though all the settings with me but I still can't send and receive emails. I was told it was bc I have other emails on Mac mail and have different ports can anyone help me get this sorted or suggest what I should do?

Cheers
wemac

I don't believe the advice you got is in any way at all correct. Each account's settings are entirely separate from other accounts.

Here's the company's own web page on how to set this up:

http://www.crazydomains.com.au/help/howto-setupmacosx/