The first thing you need to do is make sure you are properly licensed for a
public site. Public facing SharePoint 2010 sites require a SharePoint
Server 2010 for Internet Sites license in addition to regular licensing for
internal users. This is true whether the users are anonymous users or not.
Take a look at the following overview site.



sharepoint.microsoft.com/.../...nsing-Details.aspx

Thank you for your answer.
Actually i have an Enterprise License Key in My Server Farm, can i use the same
to host my SharePoint Site.
Also in case, I already have the Internet License Key. But, when i go to Convert
Farm License Type It's disabled and i cant type anything in the License Box.

I Appreciate your Answer And Reply ASAP.

First have your ISP route the url to an external IP on the server.

Next, configure alternate access mappings first:

technet.microsoft.com/.../ff679917

If that doesn't work, change the host headers in IIS.

I see people say "change the host headers in IIS" sometimes in reference to this
issue.

You need to add an AAM and add the host header in IIS if you are using host
headers with SharePoint sites. AAMs are used by SharePoint, but host headers
are used by IIS. You need both.

These are ways that you can solve your problem:

1. Use Alternate Access Mapping.
2. Try to change the DNS mapping details.

I would pefer 1.