Error "Protected with ionCube encoder"

My web site is not working suddenly on 7-7-2007 IST 10.00am.

The browser shows " Application is protected with ionCube encoder but ionCube loader is not installed or your Web server does not support dynamic libraries loading. Please contact your hosting provider."

Cart admin also not opened. I am deleted the all files in the dir public_html and try to do fresh installation; still I am getting the same message.

How it is happened?

Now please guide me how to reinstall the cart.

What are the producers I have follow in feature.

Error in the server