Moving to light room.
Please make sure that you have Read/Write access of the Destination where you are putting the files.
Or try to Add (Choose Add from the file handling option as highlighted in the picture below) a File from desktop to Lightroom catalog to see if it works(this will allow us to confirm whether the issue is when you Copy files)
Appreciate the suggestion but it didn't work. However, it has led me to a work around. In case anyone else picks up this thread: I selected the files i wanted to import directly from the SD card and then chose "open with" and lightroom. It then allowed me to import. Not the exact solution I was hoping for but at least it's a work around.