I have installed a network/windows domain called dsajn.net on a w2K3 server. I also have a internet domain www.dsajn.net at my ISP. When I log in to my windows domain and try to browse www.dsajn.net in internet explorer, I can't se that page and it looks like it routes it to my windows domain. Is there somewhere in the DNS i need to change that it should route that path out to internet?

Is there somewhere in the DNS i need to change that it should route that path out to internet? Yeah, change your domain to something that doesn't conflict with the real domains. Properly configured, Win2K3 will change your Internet domain to point to your Win2K3 server. For everyone.

But the thing is that I do not want to reinstall the domain (it is 40computers running on that and it will take to much time to reconfuguring then)

All you have to do is add a dns entry to point to the www IP address. Here is how: Start Menu go to administrative tools and choose DNS..it will bring up DNS MGT. Left hand side of pane you should see your Domain Name. Underneath you will see a folder (Forward Lookup Zone), expand it and you should see a folder with your Domain Name and click on it. Now in right hand side of pane you should see folder and notepad icons. If there is already a notepad icon with www open that up and just put the IP address of your website in there. if there isn't a www entry right click on the right hand side of pane and select new host. you will type www for the name and then add the IP address for your web site and select add host and that should work.