What caching plugin you are talking about? If you have one I recommended to remove the plugin and use the one provided by x10 instead.
Recently x10 made changes to htaccess file configuration, some code is not allowed which might result in this. do a backup of your htaccess code before you...
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India is not whitelisted on x10, so you must logging from US or a whitelsited account and looks like youre suspended too. Maybe staff can clearly more.