The most common reason you are unble to access your site/email is the IP address you are connecting from has been temporarily listed as a banned IP on the server firewall (due to multiple invalid cpanel/email attempts).
The reason for this security policy to prevent unauthorised access to accounts on the server.
Once listed in the banned IP list you will not be able to access CPanel, WebMail, POP3 email , etc. for a short period of time (normally 15 minutes).
If you have been blocked multiple times your IP may be listed perminantly in which case please raise a support ticket to discuss the issue providing your IP address (please visit http://whatsmyip.astutium.com/ if you are unsure of your current IP address).
