After an import finished the recursiveDirectoryCleaner helper deletes the _tempImport directory and its contents.

Under Windows the contents of _tempImport are deleted, but the directory itself can not be deleted, because Windows complains, that it is not empty. Despite it acutally is empty (I did exit the code directly before the warning appears and checked the dir and it is empty. I tried to enter a sleep  of 3 sec before trying to remove the directory in case something is slow, and it still warns, but the dir is empty.