sorry for the confusing topic title. What I want to do: On the edit.php page in wp-admin I have added additional links. Now, one of these links should open a file in a thickbox. So far, no problem.
That file in the thickbox should be able to use all the WP functions. How do I do that? I've put that file inside my plugin directory. When adding require(admin.php) inside that file, it doesnt find the wp-config.
How can I use all the WP functions in that file?