I installed tribalcms below my document root in a subdirectory called tcms. However, after creating a new menu item for the first time there's a link on the main page that says "To create a page in this location, please click the Edit icon below:". When you click the edit icon it expects cmspopouts/ to live at the document (eg. /cmspopouts) Mine is at /tcms/popouts.
10:47PM UTC on May 08 2007 in Tribiq CMS