Yesterday my site went down with a 503 error which I assumed was a hosting issue. I sent in a ticket and this morning was notified that the server was restarted but my site still would not work. I disabled my plugins one by one until I found that Front-End-Users was the issue. Is there a security breach in this plugin? Or does anyone know why it would bring a site down? I renamed and downloaded the plugin again. It works as intended once again.