In previous versions I have used scripts that run the "calibredb add" function while Calibre gui and server are running. I searched around and I have not seen any change in features that prevents this from happening. Based off of another loosely related post, I enabled "Allow un-authenticated local connections to make changes" and this did not change anything. I attached a picture of the example cmd prompt command I am using and the results.
Thanks in advanced. I feel like I'm missing something obvious