I have a different take on this. You may be suffering from shell escapes. Your file path contains shell escapes which are not interpolated when passing through the shell. The Windoze \ path delimiter is being seen by the shell as a line continuation character. So the shell hangs waiting for another line (thus the return), then you still need to exit the shell ( thus the Ctl-Z ).

Also, beware Open will correctly munge / vs \ in your file path where backtics will not.