One of the common reasons we have support tickets submitted is from people who have “locked themselves out” of their sites. e.g. I cannot access my website or domain, my website or domain is down or not working, I cannot login to cPanel or DirectAdmin, I cannot connect to my server, I cannot send or receive email etc.
One of the security systems we employ on the Firewalls for our servers guard specifically against "brute force attacks". These are where someone (or more usually an automated script) keeps repeatedly trying different username and/or password combinations to access your account. i.e. they keep trying to guess your password for cPanel, email, FTP etc.
Once a certain number of failures have been recorded against a particular service for your account our systems will block the offending IP address from accessing the server.
This is a security measure similar to a cashpoint machine retaining your bank card if you try the wrong PIN a certain number of times (typically 3). Otherwise, hackers could just keep on trying different usernames and passwords until they gain access to your account - "brute force".
Unfortunately, some of our customers also make the simple mistake of repeatedly trying the wrong username and password combination, hence resulting in their IP being blocked from accessing the server that their site is hosted on.
Additionaly, some FTP clients will "scan" for open ports on the server, rather than just trying to connect to the authorised FTP port (port 21). This "port scanning" activity will result in a block being applied to that originating IP address.
We have "locked down" any vulnerable ports and only authorised ports are available for users to access their services. Therefore if anyone is "port scanning" and trying to connect to unauthorised ports on the server their IP address will be blocked.
If you think that this has happened to you please email support with the IP address that you are currently using to connect to the internet.
Alternatively you could try to reboot your router (i.e. reset your internet connection) as this typically allocates a fresh IP address for you. However, this does not alter the fact that if you continue to "behave in a suspicious manner" that IP address will also be blocked.