Getting 500 Internal Server error when installing FileVista 4 on web subfolder

I am trying to install FileVista 4 to a subfolder location on my web site.  For example: http://www.myexamplesite.com/filevista.  When I try to access the site I get a 500 Internal Server Error.  I tried turning off custom error pages but that did not help.  Any ideas on how to fix this issue?

Please make sure you are setting that subfolder as "Application" in IIS manager. Also the related application pool must run .Net Framework v4.0 for FileVista 4.1 and .Net Framework v2.0 for FileVista 4.0.

I did convert the folder to an applicaton but I still get a 500 internal server error.  Looking for more suggestions.

In IIS Manager, select FileVista application folder, double click on Error Pages (under IIS group).  You should see a list of all error status codes. Click on Edit Feature Settings on the right pane.... and change Error Responses to "Detailed Errors".  Click OK and try accessing FileVista again. Now you should see a detailed error message at least so that we can find the cause.