Accessing PS with PP through firewall

[SizzleMaster]

I've never been able to access the project server using project pro 2003
versions on both. I recieve the error below. I can't access it using the
domain\administrator account which is the main account for PS inside or
outside the firewall. I'm not sure if this is a firewall issue. Any help
would be GREATLY appreciated.

The server at 'http://FQDN/Projectserver' returned the following error to
Project.

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You are not authorized to view this page
You do not have permission to view this directory or page using the
credentials that you supplied because your Web browser is sending a
WWW-Authenticate header field that the Web server is not configured to
accept.
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Please try the following:

a.. Contact the Web site administrator if you believe you should be
able to view this directory or page.
b.. Click the Refresh button to try again with different
credentials.
HTTP Error 401.2 - Unauthorized: Access is denied due to server
configuration.
Internet Information Services (IIS)
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