SBS 08 Ex 07 POP3 Issues

Morning all Noobie here

I have just upgraded from SBS03 to SBS08 and despite some teething issues I have fumbled my way through some stuff BUT I finally got External mail SMTP working and thought that I had External POP3 going as well but NOOOOO.
I setup a test account on my isp eg: bob@isp.com and sent it a few emails for testing. After getting the SBS test account setup I thought I'd see and BANG I received all emails sent to the bob account. So I thought great I'll shoot it another email from a different email source but I have never received it or the other emails.
My test email is still sitting at the ISP and when I do to retrieve emails through pop3 I get a error and to view Event, when I get to event there is nothing there to reflect a pop3 activity.

Any ideas would be great as to why working 1 minute and not the next? I want to have several accounts on SBS all using external mail @ same ISP.

Thanks