HTTP Error 403.14 - Forbidden

Total Newbie.  Just installed WebMatrix on Windows 8.  The saple site that comes with WebMatirx runs fine from the folder in MyDocs.  But when I set up a new site, and tried to run it I got " HTTP Error 403.14 - Forbidden "

The Info on the 403.14 page suggested I run appcmd set config /section:system.webServer/directoryBrowse /enabled:true  andappcmd set config ["SITE_NAME"] /section:system.webServer/directoryBrowse /enabled:true 

What do I need to do to get the file to run in the way the above instructions require?

Thanks

JohnJeff