File Manager not working

I uploader a script to my server via ftp and now when I try to delete the entire folder/directory there is a folder on there that can not be deleted.

This happen before and the only way I was able to delete the folder was by going to Virtualmin’s File Manager and deleting it from there. The problem now is that when I go to File manager the page is blank, (no toolbar or menu) it don’t show anything at all.

It’s like file manager does not exist. Can anyone help me get File manager back? Thx