I have Excel Services 2010 configured for trust for an entire site collection,
trusting all children.

The web front end(WFE) server is called SERVERNAME1. There is only one WFE.
People in the organization access the via http://INTRANETNAME.
There is an alternate access mapping for INTRANETNAME.

When I go to an excel spreadsheet using INTRANETNAME I get the following
message:

"This workbook cannot be opened because it is not stored in an Excel Services
Application trusted location."

If I replace INTRANETNAME with SERVERNAME1 and resubmit the url, it works.

Any ideas as to what the problem could be?