Help. Cant send or receive mail using Windows Mail Programme

[#1]

Please can anyone help. I have just switched to Plusnet. My email is working well, and I can send and recieve mail to my computer.
My husband has created an emai account for himself (I am the main account holder) However he cannot send or receive emails from Plusnet to his computer. He uses Windows Mail on his computer.Naturally he doesn't want his mail coming to my computer, and he wants to be able to send mail too. At the moment he has opened himself a hotmail accouint so that he can receive mail, but then has to go onto Hotmail to send a reply. Not what he wanted at all.
Has anyone else encountered this problem?
Any advice would be most welcome.
Thanks in anticipation
Margwxs

[#2]

I think he probably isn't using the correct format for the email account on the computer
The logon information is as follows
email address husband@username.plus,com
Incoming mail server (POP3) mail.plus.net
Outgoing mail server (SMTP) relay.plus.net
Username username+husband
Password - as set up
In the above
husband is the name of the email account he has set up
username is your account username
Password is either the one set up when the email was created or if one wasn't the password for the main account

[#3]

Just to be clear .... what your husband needs is his own mailbox set up on your account.
  Go to your Members Centre > Email Settings > Manage My Mail. Now click the tab Mailboxes -- don't be tempted by the obvious button to set up a New Account -- that is the step where you might start to go wrong!  Enter HisMailboxname, and HisPassword for this mailbox, where indicated. The email address for this mailbox is HisMailboxname@YourUsername.plus.com .
  Now set up your husband's email client to collect from YourUsername+HisMailboxname, using HisPassword, and the same server settings as you use. He can also access his mailbox in Webmail using these terms.
Hope this helps, and I'm not just teaching granny to suck eggs 
Chris