unable to view the external hosted website without www.

none of the employees were able to see the website internally. Externally it is fine. There are also still a handful of employees that can hit the site without a problem. The majority of use are getting an IIS message that says the site is under construction. There were no changes made that would have caused this. We are running Microsoft Exchange that has Outlook Web Access that uses IIS. Our website is hosted by an outside company. The domain name is a .com but I made an (A) record with www that allowed us to hit the site. Can anyone please help me????