Error setting up Apache Http Server Virtual Server?

I set up a virtual server at the following address with Apache:
http://dev.local/dev_test.php

and yet when I try to access it, I get the following error:
Forbidden

You don't have permission to access /dev_test.php on this server.

Yet I can access the same file in htdocs without any difficulty. Why is this?
Arug! now I only get it for php files.

if you can access the SAME file using a different locater, it means your DocumentRoot isn't properly set up.

edit your httpd.conf file, and find the DocumentRoot section, and change it to whatever folder 'dev_test.php' is in. Then simply restart apache, and it should work. (assuming permissions are okay: if it's on windows, they should be fine. on linux, chmod them to 755)

Let me know if you need more help.
-Eric