login.html.1

Why am I getting these pages created every 5 mins outside the root on my server? I log into my ftp, and there are literally, hundreds of these (login.html.xxx) pages..one created every 5 mins, numbered incrementally . They average around 40kb each. Its a pain to have to go in and delete them every day!

I have attached one of these pages.. I have changed the url in it.