I have had other people say, on another forum, that moz is banning accounts.
Moz is probably getting hammered with requests after google shut down page rank as moz is the biggest free metric provider. Moz lowered their monthly limit from 1 million to 25K. Then they installed incapsula to block a loads of legitimate requests.
Scrapebox found a way to bypass the firewall and now Im guessing they are banning accounts. Someone else said they created 1 moz account on several different servers and were using with the ips of the servers they created on and moz was banning all their accounts.
So try and login on the moz site, is it banned? You can mail moz, although you might avoid mentioning your using it with scrapebox.
But you can try a new moz account with a new ip and see if it works.
Also it might not be any of that, it might be a router firewall or anti-virus or software firewall etc.. that is just blocking your connection.