Not necessarily. There are few things you must know ;
1) If you have continuously keyed-in wrong username, password, etc.. the firewall will identify this as an intrusion attempt. Your IP will be blocked permanently.
2) If your connection with the server is too high (more than 250 connection from your PC into the server), firewall will identify this 'Attacks'. Your IP will be blocked for 30 minutes for every offence.
* If you are blocked by the reason above, you may fix it immediately by turning your modem 'OFF' and 'ON' (by disconecting & connecting), to get a new IP. You can also contact us, stating your PC IP. If you are using a dedicated IP, you need to contact us to unblock the IP.
* If you are really sure that you did not do the above mistakes, and still can't access your website, you may try to ping your domain from other place (via domaintools.com, for example). If ping is OK, and you are using a Dynamic IP, maybe the IP has been blocked due to misuse by previous user. Try to reset it & contact us, together with the IP info.