I have a subdomain pointed at my server and in IIS 7.5 have a site set up for it which works fine.
If I navigate to http://test.example.com the default index.php page loads as it should.
I also have a sub-section of the site located at http://test.example.com/viewer
This also has a default index.php page, however when I navigate to that URL, I get a 404 error. Entering the full path to the index file (i.e. .../index.php) loads fine.
I have checked the default document for both the root and the subdirectory, and they are the same.
Any ideas how to get the default document in the subdirectory loading?