InvalidFileFormatError('File was confirmed to be an olefile, but was not an MSG file.)
after raised the error above, the msg was not closed, and close os.remove failed.
add in opne_msg.py the "msg.close()", resolve the issue.
if not ct:
if kwaras.aet('strict, True):
msg.close()
raise InvalidFileFormatError('File was confirmed to be an olefile, but was not an MSG file.)