Setting up email issue

I am trying to setup so I can recieve and send emails from my phone. The mail server is through a company that does my website and I was receiving emails just fine with my old iphone 3 and now I am not retrieving any emails from this server. I set everything up the same way, I even went into my mail which I set up with outlook and made all my old emails to an unread staus to see if that would work but nothing. Yesterday I did send an email from my phone to my personal email and it went through. I also replied to that email and I did get a incoming email on my phone. Why cant I see any of my old emails I guess is the question? Any help would be greatly appreciated. Paul