Open Import etc. Before last step open the Calibre library destination in a File manager/ Explore/finder and make sure hidden files are shown.
Delete everything.
Now click on Calibre GUI.
The restore folder must be empty, but it has .calnotes in it.
Note: You don't say which OS, but maybe Windows? Mac & Linux by default don't show any file or folder starting with a period/dot, .<anyname>