Is it permissible to send a song with a voice free of musical instruments to a friend online, and then delete it?

A woman is permitted to chant permissible anashid (religious songs) and for other women to hear them. However, they should not be sent as recordings over the internet for fear of non-mahram men hearing them. Similarly, recording them is not advisable because the recording might fall into the hands of someone for whom it is not permissible to hear it.