Web Site access

My company web site is accessable from any location on the Internet but we can not access it from the company office in WA. We are running Proxy Server 2 in the office and our web servers are located on a DMZ in our CA office. If we try to connect to www.ourcompany.com from the office, we recive an “connection refused” error.
At home I can connect easily to the web site through my DSL. Is it our Proxy or permissions on the Web Server in CA ?