Are there any banned file extensions on your servers?
ANSWER: Yes, there are several file extensions that are not allowed for security reasons. Our cron jobs will automatically scan and delete any of the above file extensions multiple times per day:
htaccess, exe, asp, aspx, jsp, com, bat, ascx, cfc, cfm, cfml, cfr, cfswf, jws, dll, vbs, reg, asis
Live list: http://mirrors.littlebizzy.com/bash/cleaner-cron.txt
Also please note that info.php or phpinfo.php files are automatically deleted also, as well as the xmlrpc.php file.