Problem when changing site from shared to dedicated IP ?

Hi all

I will explain my problem:

First I had an account om my server, let's say aaaa.com. This was created as namebased on the shared IP of my server.
The DNS for this domain was done by another firm and the A record pointed to my shared IP, everything was working great.

Yesterday I changed the account aaaa.com to a dedicated IP on my server.
Also I changed the A record for aaaa.com to the new IP on the control panel of the other firm.

Now, when I do a ping to aaaa.com, I receive responses from the new dedicated IP, so the DNS zone is updated correctly I think.

BUT when I type aaaa.com in the browser, I see nothing but 'The page cannot be displayed'.
The same thing when I enter the dedicated IP in my browser.

Does anyone know what the problem could be ? I think I have to change something on my server because I am working with a dedicated IP and zone files on another server, but I don't know what ?

All help is appreciated !

 

PROBLEM SOLVED, IP was already in use by another server !