WordPress at a glance
filter is not described

xmlrpc_login_error filter-hook . WP 3.5.0

Filters the XML-RPC user login error message.


add_filter( 'xmlrpc_login_error', 'filter_function_name_6002', 10, 2 );
function filter_function_name_6002( $error, $user ){
	// filter...

	return $error;
The XML-RPC error message.
WP_User object.

Where the hook is called

wp-includes/class-wp-xmlrpc-server.php 292
$this->error = apply_filters( 'xmlrpc_login_error', $this->error, $user );

Where the hook is used (in WP core)

Does not used.