For the last few days, I've been receiving visits to random pages on my site that don't exist. For example: my site .com/VF4YhNem/index.html .../qaRKCS9T/index.html .../CmVZBonr/index.html These are not pages on my site and would take any would be visitor to a 404 page not found page of my site. These pages are being visited by unique IP's by about 30 different ones a day. Then, for the first time ever, in about 9 years, most of my SERP's that I've been tracking are no longer top 100. Anybody have an idea of whats going on?