I inherited a site that has a lot of manually created html/php files in subfolders outside of Drupal. In other words, not as nodes, but static html/php fiels (leading of from the site root). I would like to move many of them inside Drupal as nodes because they are just some basic html/php. However, when I create a node using the same alias, it continues to load the old static html/php page. (I have flushed cache, both local and in drupal). Thoughts?
You'll need to remove the original file, or make it unreadable by your webserver. Drupal is basically a big 404-handler; if the file exists it will get loaded before the webserver looks for the default index.php which then bootstraps Drupal.
That, or check to make sure you don't have APC or similar opcode cache installed.
Have you checked for redirects in your
.htaccess file? It's a possibility they are being redirected before Drupal even starts bootstrapping.
Try moving this file away form your webroot (back it up first, just in case) and then get a fresh
.htaccess file from whichever Drupal 6 version you are running.