No warranty, use at own risk.
Go to the file:
<your wp root dir>/wp-includes/pluggable.php
around line 358
* Filters the name to associate with the “from” email address.
* @since 2.3.0
* @param string $from_name Name associated with the “from” email address.
$from_name = apply_filters( ‘wp_mail_from_name’, $from_name );
$from_name=’no-reply’; //end of mod
$phpmailer->setFrom( $from_email, $from_name );