One step towards making your shop more secure is to change the default admin route from http://www.your-shop.com/admin to something more secure and less guessable. The route must be changed in app/etc/local.xml.
After adding that to your app/etc/local.xml file, clear the cache and check if your admin is now available at http://www.your-shop.com/your-new-backend-route instead of http://www.your-shop.com/admin.
Changing the admin route for security reasons
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