UPDATE 1:
Basically, from a computer outside the network, I can access the website by typing into the browser address bar, either of the following, which is how it should be:
http://www.companyname.com
http://companyname.com
However, from within the company network, we can only access the external website by typing in
http://www.companyname.com
It will not work if I type
http://companyname.com
ORIGINAL QUESITON:
Our internal network has the same domain name as our external website, lets say it's companyname.com for both the website and for our internal network.
This is causing problems because I am unable to access the companyname.com website from within the network. I have to use a computer from outside the network to see the website.
Is there a way around this issue, ideally without having to change the internal or external domain names?